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521 Cards in this Set
- Front
- Back
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Catabolic Reactions
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Metabolism
Break down large chemicals and release energy |
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Anabolic Reactions
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Metabolism
Build up large chemicals and require energy |
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Absorption
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Passage of nutrient molecules through the lining of the digestive tract into the body. Absorbed molecules pass through cells lining digestive tract via diffusion or active transport.
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Transport
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Circulation of essential compounds required to nourish the tissues and removal of waste products from tissues.
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Assimilation
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Building up of new tissues from digested food materials
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Respiration
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Consumption of oxygen by the body. Cells use the oxygen to convert glucose to ATP.
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Synthesis
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Creation of complex molecules from simple ones.
Anabolism |
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Homeostasis
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Regulation by hormones and the nervous system of the body to maintain its internal environment in changing external environment
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What elements are the primary components of living things?
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Carbon
Hydrogen Oxygen Nitrogen Sulfur Phosphorus |
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What are some components (elements) of the protoplasm?
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Magnesium
Iodine Iron Calcium |
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What are carbohydrates composed of?
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Carbon, Hydrogen and Oxygen in a 1:2:1 ratio
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Uses of carbohydrates
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Store energy: glucose and glycogen (animals) or starch (plants)
Structural molecules |
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How are disaccharides and polysaccharides formed?
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Dehydration synthesis
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Example of monosaccharides
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Glucose
Fructose |
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Example of disaccharides
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Maltose
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Example of polysaccharides
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Cellulose
Starch |
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Composition of lipids
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Three fatty acid molecules bonded to a glycerol backbone.
Do not form polymers |
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Fatty Acids
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Composed of long carbon chains that make them hydrophobic and carboxylic acid groups that make them acidic.
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Are polysaccharides water soluble?
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No
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Role of Lipids
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Chief means of food storage- release more energy per gram weight than any other biological compounds.
Provide insulation- major component of fatty tissue (adipose) |
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Phospholipids
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Contain glycerol, two fatty acids, a phosphate group and nitrogen-containing alcohol
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Waxes
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Esters of fatty acids and monohydroxylic alcohols
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Steroids
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Have three fused cyclohexane rings and one fused cyclopentane ring
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Examples of steroids
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Cholesterol
Sex hormones Corticosteroids |
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Carotenoids
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Fatty acid like carbon chains with conjugated double bonds carrying six membered carbon rings at each end
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Carotenes and xanthophylls are
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subgroups of carotenoids
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Poryphyrins
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Contain four joined pyrrole rings that are often complexed with a metal.
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Protein composition
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Polymers of amino acids
Composed of C, H, O,and N and sometimes P and S |
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Peptide bonds join together ___________ via ____________ reactions
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Amino acids
Dehydration |
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Primary Structure of Proteins
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Sequence of amino acids
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Secondary Structure of Proteins
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Proteins coil and fold to form alpha helices and beta-pleated sheets
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Argininine, Lysine and Histidine are examples of
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Proteins
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Simple proteins
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Composed entirely of amino acids
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Albumins and Globulins
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Functional proteins that act as carriers or enzymes
Globular in nature |
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Scleroproteins
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Fibrous structural proteins
Example: collagen |
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Conjugated Proteins
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Contain a simple protein portion plus at least one nonprotein fraction
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Mucoproteins
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Protein bound to a carbohydrate
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Chromoprotein
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Protein bound to pigmented molecules
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Metalloproteins
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Protein complexed around a metal ion
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Nucleoproteins
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Proteins containing histone or protamine bound to nucleic acids
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Function of Hormones
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Chemical messengers secreted into the circulation
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Insulin and ACTH are examples of
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Hormones
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Enzymes- Function
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Biological catalysts
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Structural Proteins
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Extracellular or intracellular proteins that contribute to physical support of cell/tissue
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Transport Proteins
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Carriers of important materials
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Antibodies
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Bind to foreign particles
Proteins |
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Substrate
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Molecule on which an enzyme acts
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Active Site
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Area on enzyme where substrate binds
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Lock and Key Theory (enzyme function)
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Enzyme function
Spacial structure of enzyme's active site is complementary to spatial structure of substrate. Largely discounted |
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Induced Fit Theory (enzyme function)
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Active site has flexibility of shape. Conformation changes when appropriate substrate comes in contact
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Are enzyme reactions reversible?
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Yes
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Hydrolysis Reaction- Function
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Digest large molecules into smaller components
Involve enzyme use |
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As temperature increases, rate of eznyme action
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Increases up to an optimal temperature which could deactivate the enzyme by denaturing it
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How does pH effect enzyme activity?
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There is usually an optiaml pH above and below which enzymatic activity declines.
Usually 7.2 is optimal pH |
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Lactase
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Enzyme that hydrolyses lactose to monosaccharides glucose and galactose
Hydrolysis reaction |
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Proteases
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Enzyme that degrades proteins to amino acids and lipases
Hydrolysis reaction |
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Synthesis Reactions- Function
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Growth, repair, regulation, protection and production of food reserves.
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Cofactors
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Nonprotein molecules required by some enzymes for them to become active
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Prosthetic Groups
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Cofactors which bind to the enzyme by strong covalent bonds
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Nucleic Acids- Composition
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Contain elements C, H, O, N, P
Polymers of nucleotides |
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Function of nucleic acids
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Code all of the information required by an organism to produce proteins and replicate
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Cell Theory
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All living things are composed of cells
Cell is basic unit of life Cells arise from pre-existing cells Cells carry genetic information in the form of DNA which is passed from parent to daughter cell |
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Resolution
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Differentiation of two closely situated objects
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Types of Microscopes
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Compound Light Microscope
Phase Contrast Microscope Electron Microscope |
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Compound Light Microscope
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Uses two lenses or lens systems to magnify objects
Kills specimen |
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Phase Contrast Microscope
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Permits study of living cells
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Electron Microscopy
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Uses beam of electrons to produce higher magnification than other microscopes.
Usually not used to examine live specimen |
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Centrifugation
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Used to separate cells or mixtures of cells without destroying them by spinning the fragmented cells at high speeds
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What parts of the cell membrane move freely within the membrane?
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Lipids and Proteins
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Is the cell membrane permeable to water?
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Yes, it is a small molecule like Oxygen
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Carrier Proteins
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Assist large, charged molecules in crossing the membrane
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Histones
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Complexed with DNA to form chromosomes
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Nucleolus
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Dense structure in nucleus where ribosomal RNA synthesis occurs
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Glycosylation occurs in the
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Golgi apparatus
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Mitochondria are the sites of
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aerobic respiration
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Cyclosis
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Transport with in the cytoplasm
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Vacuoles and Vesicles
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Membrane bound sacs involved in transport and storage of materials
Vacuoles- plant cells |
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Centrioles
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Specialized microtubule involved in spindle organization
Plant cells do not have centrioles |
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Hydrolytic Enzymes
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Used for intracellular digestion
Found in lysosomes |
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Difference between plant cells and animal cells
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In plants:
no centrosome cell wall of cellulose chloroplasts many vacuoles or one large vacuole |
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Osmosis
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Simple diffusion of water from low solute concentration to high solute concentration
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Lysis
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When water flows from hypotonic solution to inside of cell causing it to burst
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Facilitiated Diffusion
Passive Transport |
Net movement of dissolved particles down their concentration gradient through channels or carrier proteins in cell membrane
Does not require energy |
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Active Transport
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Net movement of dissolved particles against their concentration gradient with help of transport proteins
Requires energy |
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Brownian Movement
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Movement of particles due to kinetic energy which spreads small suspended particles throughout cytoplasm
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Cyclosis/Streaming
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Circular movement of cytoplasm around cell transport molecules
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Diffusion
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Means of transport for food and oxygen from the environment to the cells
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Circulatory System
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In complex animals- vessels transport fluid and a pump drives circulation
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What are the two means of movement of materials?
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Diffusion or a circulatory system
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Karyokineses
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Nuclear division
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Cytokinesis
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Cell division
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Interphase
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90% of cell life
Each chromosome is replicated forming two sister chromatids held together in the centromere Individual chromosomes are not visible- chromatin |
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Prophase
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Chromosomes condense and centriole pairs separate and move towards opposite poles
Spindle apparatus forms and nuclear membrane dissolves |
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Metaphase
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Spindle fibers attach to chromatids aligning them at the center of cell forming metaphase plate
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Anaphase
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Sister chromatids separate and are pulled toward opposite poles
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Telophase
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Spindle apparatus has disappeared
Nuclear membrane forms around newly formed chromosomes Chromosomes uncoil resuming interphase form |
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Cytokinesis
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Cytoplasm divides into two daughter cells and cleavage furrow forms separating two nuclei.
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Plant Cell Division
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Plant cells lack centrioles
Do not form cleavage furrow- divide by formation of cell plate |
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Difference between mitosis and meiosis?
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Mitosis preserves diploid number of cell, meiosis produces haploid number and produces four haploid gametes
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Prophase I
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Chromatin condenses, spindle apparatus forms.
Chromosomes come together and intertwine Crossing over takes place. |
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Synapsis
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Process in which homologous chromosomes come together and intertwine
Meiosis- prophase I |
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Tetrad
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Meiosis I- prophase I
Name given to each synaptic pair of homologous chromosomes. Contains four sister chromatids |
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Crossing Over
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Meoisis I- Prophase I
Process during which chromatids of homologous chromosomes break at corresponding points and exchange equivalent pieces of DNA. |
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Does crossing over take place between homologous chromosomes or sister chromatids?
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Homologous chromosomes
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Anaphase I
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Homologous pairs from each tetrad separate and are pulled to opposite poles.
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Disjunction
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Each chromosome of paternal origin separates from homologous maternal origin chromosome and can either chromosome can end up in either daughter cell.
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What are the four types of asexual reproduction?
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Fission
Budding Regeneration Parthenogenesis |
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What organisms reproduce asexually?
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All prokaryotes
Some invertebrate animals All plants |
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Binary Fission- Process
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DNA replicates and new plasma membrane and cell wall grow inward along midline dividing it into two daughter cells.
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What kinds of organisms does binary fission take place in?
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One-celled organisms
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Budding- Process
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Cell membrane pinches inward forming new, genetically identical (to parent cell) cell that is smaller (but grows to adult size). The new cell may separate from arent or remain attached
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Regeneration- Process
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Regrowth of lost/injured body part via mitosis of cells.
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Parthenogenesis- Process
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Natural process of the development of an unfertilized egg into an adult organism.
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What are the two means of asexual reproduction in plants?
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Spore formation
Vegetative propagation |
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Alternation of Generation
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A diploid generation is succeeded by a haploid generation
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Spore Formation- Process
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Diploid sporophyte generation produces haploid spores that develop into haploid gametophyte generation.
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What are spores?
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Specialized cells with hard coverings that prevent the loss of water
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Vegetative Propagation- Process
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Undifferentiated tissues in plants provide a source of cells that can develop into an adult plant without genetic variation.
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Meristems
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Undifferentiated tissues in plants
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Bulbs (Natural Vegetative Propagation)
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Split to form several bulbs
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Tubers (Natural Vegetative Propagation)
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Underground stems with buds.
Can develop into adult plants |
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Runners (Natural Vegetative Propagation)
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Stems running above and along the ground extending from main stem.
Can produce new roots and upright stems |
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Rhizomes (Natural Vegetative Propagation)
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Woody underground stems
Can develop new upright stems |
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Auxins (Artificial Vegetative Propagation)
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Synthetic plant hormones.
Used to accelerate root formation from a cut piece of stem. |
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Layering (Artificial Vegetative Propagation)
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Stems of certain plants are bent to ground where they take root
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Scion-stock connection (Artificial Vegetative Propagation)
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Stem of one plant (scion) is connected to rooted stem of another related plant (stock). Cambium tissues are in contact.
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What are the three things sexual reproduction requires?
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1. Production of functional sex cells (gametes) by adult organisms)
2. Union of sex cells (fertilization) and formation of a zygote 3. Development of zygote into another adult |
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Gonads
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Specialized organs that produce gametes
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Male gonads?
Female gonads? What do they produce? |
Testes- sperm
Ovaries- oocytes |
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Hermaphrodites
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Have both functional male and female gonads
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Spermatogenesis- what and where?
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Sperm production
Seminiferous tubules |
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Spermatogenesis- process
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Diploid cells (spermatogonia) undergo meiosis producing four haploid sperm.
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Structure of Sperm
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Elongated cell with head made almost entirely of the nucleus with paternal genome in it, a tail (flagellum), neck and body
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Oogenesis- what and where?
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Production of female gametes
Ovaries |
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Oogenesis- Process
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Diploid primary female sex cell undergoes meiosis in ovaries to produce a single mature egg.
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Polar Body
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Produced during oogenesis.
EAch meoitic division makes small cells with little more than nucleus. |
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Mature Ovum- Structure
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Large cell with most of cytoplasm (from meiotic divisions)
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Fertilization
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Union of the egg and sperm nuclei to form a zygote with diploid number
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External Fertilzation- where?
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Occurs in vertebrates that reproduce in water.
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External Fertilization- Process
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Female lays eggs in water
Male deposits sperm in vicinity Lower chances of fertilization so many eggs are layed |
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Internal Fertilzation- where?
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Terrestrial vertebrates
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Internal Fertilization- Process
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Direct route for sperm to reach egg cell- higher chances of success so females produce fewer eggs.
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Pathway of sperm
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Seminiferous tubules to
Epididymis to Vas Deferens to Ejaculatory Duct to (nothing) Urethra to Penis SEVEN UP |
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Where are the testes located? Under what conditions?
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In external pouch- scrotum
Testes maintained at temperature 2-4 degrees Celsius lower than body temperature. |
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Where is testosterone produced?
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Testes
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What does testosterone do?
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Regulates secondary male characteristics- hair, voice
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Where are the ovaries located?
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In the abdominal cavity below the digestive system.
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What are the ovaries made of?
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Thousands of follicles (mulitlayered sac of cells)
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What produces estrogen?
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Follicle cells of ovaries
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How often is an ovum released from the ovary? Where is it released to?
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Once a month
Into the abdominal cavity to the oviduct |
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Fallopian tubes open up into the __________
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Uterus
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Cervix is the
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end of the uterus
site of sperm deposition passageway for baby to be expelled |
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What regulates the secretion of estrogens and progesterone?
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LH and FSH
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What are the two female sex hormones?
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Estrogen
Progesterone |
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What does GnRH do? (ovaries)
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Regulates LH and FSH in ovaries
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Estrogens- role
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Necessary for normal female maturation
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Progesterone- role
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Stimulates development and maintenance of endometrial walls in preparation for implantation
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Menstrual Cycle- phases
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Follicular
Ovulation Luteal Phase Menstruation Freakin OLd Man |
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Follicular Phase of Menstrual Cycle
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Follicle simulating hormone promotes development of the follicle which grows and starts to secrete estrogen
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What triggers ovulation?
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LH surge at midcycle
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Ovulation- what happens?
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Mature ovarian cycle bursts and releases an ovum.
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LH
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Luteinizing hormone
Female rep. |
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FSH
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Follicle Stimulating Hormone
Female rep. |
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Luteal Phase
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Ruptured follicle develops into corpus luteum which secretes estrogen and progesterone.
Progesterone produces secretions to prepare endometrium glands for implantation of embryo |
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Menstruation
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If ovum isn't fertilized, corpus luteum atrophies causing drop in progesterone and estrogen levels causing endometrium to slough off=menstrual flow.
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Menstruation- what happens if fertilization occurs?
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Developing placenta produces hCG (human chorionic gonadotropin) maintaining corpus luteum
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Does the sporophyte or gametophyte generation dominate in plants?
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Sporophyte
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Gametophyte Generation in Plants
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Haploid gametohpyte generation prouces gametes by mitosis. Union of male and female gametes at fertilization restores diploid sporophyte generation
SEXUAL REPRODUCTION |
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Sporophyte Generation in Plants
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Diploid sporphyte generation produces haploid spore by meiosis which divide by mitosis to produce the haploid or gametophyte generation
ASEXUAL REPRODUCTION |
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Angiosperms
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Flowering plants
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Stamen- What? Components
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Male organ of flower
Consists of stalk-like filament with terminal sac called anther |
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Anther- What? Where?
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produces haploid spores
Stamen |
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Pistil- What? Parts
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Female organ of flower
Stigma, style and ovary |
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Stigma- What?
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Sticky, top part of pistil
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Style- What?
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Tube-like structure connecting stigma to ovary in pistil
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Ovary of Angiosperms
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Enlarged base of pistil
Contains one or more ovules |
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Sepal- What? Role
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Green leaves
Cover and protect flower bud during early develoment |
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The male gametophyte of angiosperms is____
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the pollen grain
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Pollen Grain (Angiosperms)
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Contains a tube nucleus and a generative nucleus formed by mitosis of a microspore.
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How are the male gametes of angiosperms formed?
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Pollen grains are transferred from the anther to the stigma where the generative nucleus divides forming sperm nuclei
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Where does the female gametophyte of angiosperms develop?
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In the ovule from one of four spores
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What does the embryo sac of angiosperms contain?
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two polar endosperms and an egg nucleus
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How does fertilization in angiosperms occur?
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Sperm nuclei enter the embryo sac. One sperm nucleus fuses with the egg nucleus to form the diploid zygote which develops into the embryo.
The other sperm nucleus fuses with the two polar bodies to form the endosperm= food for embryonic plant. |
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Components of the embryo:
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Epicotyl
Cotyledons Hypocotyl Endosperm Seed Coat |
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Epicotyl (Angiosperm embryo)
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Precursor of upper stem and leaves
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Cotyledons (Angiosperm Embryo)
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seed leaves
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Hypocotyl (Angiosperm Embryo)
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Develops into lower stem and root
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Endosperm (Angiosperm Embryo)
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Grows and feeds embryo
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Seed Coat (Angiosperm Embryo)
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Develops from outer covering of ovule
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What is the means of seed dispersal in angiosperms?
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In the form of fruit- enables seed to be carried by air, water or animals until its release
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Apical Meristem
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Found in tips of roots and stems- growth in length occurs here
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Lateral Meristem
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Located between xylem and phloem. Tissue here permits growth in diameter.
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Alleles are
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Alternative forms of a gene
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Where do the two alleles for each inherited trait in an organism come from?
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One allele is inherited from each parent
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What happens to the two inherited alleles during meiosis?
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They segregate, resulting in gametes with only one allele for any given trait
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Mendel's Law of Dominance
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Dominant allele appears int eh phenotype
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F in F generation
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Filial
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Testcross
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Used to predict the genotype of a dominant phenotype.
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Mendel's Law of Independent Assortment
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Crossing over exchanges information between chromosomes and can break the link of certain patterns of genes that stay together during crossing over.
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Incomplete Domiance
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When phenotypes are a blend of parental phenotypes. The phenotype of the heterozygote is an intermediate of the phenotypes of the homozygotes
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Codominance
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Multiple alleles exist for a given gene more than one of which is dominant. When both dominant alleles are present, both are expressed
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ABO blood groups are an example of
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codominance
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Autosomes
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All chromosomes other than sex chromosomes
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Sex-linked Genes
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Genes on X or Y chromosome
In humans usually on X |
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In males, recessive genes carried on X chromosome produce ____________ phenotype
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Recessive
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Hemophilia and Color-blindness are examples of
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Sex-linked recessive traits
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Males affected by a X-linked disorder can or cannot pass the trait onto their male offspring? female?
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cannot
can |
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Why are fruit flies so popular for genetic research?
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Short life cycle
Reproduces in large numbers Large chromosomes Few chromosomes Frequent mutations |
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Nondisjunction
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Failure of homologous chromosomes to separate during meiosis I or failure of sister chromatids to separate during meiosis II
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Trisomy
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Zygote has three copies of a chromosome.
Caused by nondisjunction |
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Monosomy
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Zygote has only one copy of a chromosome due to nondisjunction
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Down Syndrome is caused by
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Trisomy of chromosome 21
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What causes chromosomal breakage?
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Can happen spontaneously or by environmental factors
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Mutations in somatic cells can lead to ________
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tumors
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Mutations in gametes ________
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are passed on to offspring
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Silent Mutations
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Mutations in regions of DNA that don't code for proteins and are not expressed in phenotype.
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Mutagenic Agents
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Induce mutations
Examples- uv, x rays, chemical compounds |
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Phenylketonuria
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Molecular disease caused by inability to produce enzyme for metabolism of phenylalanine
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Sicle Cell Anemia
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Red blood cells become crescent shaped because they contain defective hemoglobin. Caused by substitution of valine for glutamic acid
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Purines (list)
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Adenine
Guanine "ine" |
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Pyrimidines
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Cytosine
Thymine y's in all three |
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Phosphate connects to ____________ connects to ____________ in DNA
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sugar
base |
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Semiconservative Replication
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Each new daughter helix contains an intact strand from the parent helix and a newly synthesized strand.
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The degeneracy or redundancy of the genetic code refers to
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the fact that most amino acids have more than one codon specifying them
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RNA contains __________ instead of______________
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uracil
thymine |
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mRNA
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Messenger RNA
Carries DNA complement and transports it from nucleus to ribosomes Monocistronic |
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Monocistronic
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One mRNA strand codes for one polypeptide
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tRNA
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Transfer RNA
Small RNA in cytoplasm which aids translation of mRNA's nucleotide code into a sequence of amino acids- brings amino acids to ribosomes during protein synthesis. 40 known types of tRNA |
|
|
rRNA
|
Ribosomal RNA
structural component of ribosomes. Most abundant type of RNA. Synthesized in nucleolus |
|
|
How does tRNA's structure aid the process of translation?
|
One end contains a three-nucleotide sequence (the anticodon) and the other end is the site of amino acid attachment
|
|
|
Aminoacyl-tRNA synthetase
|
Enzyme with an active site that binds to both the amino acid and its corresponding tRNA catalyzing their attachment to form an aminoacyl-tRNA complex.
used in translation |
|
|
Ribosome- Composition
|
Two subunits that bind during protein synthesis.
Four binding sites |
|
|
What are the four binding sites of ribosomes?
|
one for mRNA
three for t RNA- A, P and E A site binds to incoming aminoacyl tRNA P site binds to tRNA attached to growing polypeptide chain E site binds a free tRNA before it exits the ribosome |
|
|
In polypeptide synthesis, ribosome binds to mRNA near
|
5' end
|
|
|
Start codon
|
AUG
|
|
|
Termination codon
|
UAA
UAG UGA |
|
|
Nucleoid
|
In bacteria
Single circular chromosome can be found here. |
|
|
Plasmids
|
Small circular rings of DNA found in many bacteria.
|
|
|
Episomes
|
plasmids capable of integration into the bacterial genome.
|
|
|
DNA is synthesized in_____________ dirction
|
5' to 3'
|
|
|
Bacterial cells reproduce by
|
binary fission
|
|
|
Transformation
|
Creates genetic variance in bacteria
A foreign chromosome fragment is incorporated into the bacterial chromosome via recombination |
|
|
Conjugatoin
|
Creates genetic variance in bacteria
Transfer of genetic material between two temporarily joined bacteria. Cytoplasmic conjugation bridge forms and genetic material is transferred from + type to - type |
|
|
F Factor
|
Sex factor in bacteria
Plasmid that is necessary for conugation from F+ to F- |
|
|
Transduction
|
Creates genetic variance in bacteria
Fragments of the bacterial chromosome accidentally become packaged into viral progeny produced during infection. |
|
|
Recombination
|
Creates genetic variance in bacteria
Linked genes are separated- breakage and rearrangement of adjacent regions of DNA when organisms carrying different genes for the same traits are crossed |
|
|
Operon
|
Found in bacterial cells
Consists of structural genes, an operager gene, and a promoter gene Directs transcription |
|
|
Structural genes code for
|
proteins
|
|
|
Operator genes code for
|
nothing- nontranscribable
|
|
|
Promoter gene codes for
|
nothing- initial binding site for RNA polymerase
|
|
|
Regulation in bacteria is via ______________ systems or ________________ systems
|
inducible
repressible |
|
|
Inducible systems of regulation
|
in bacteria
require presence of an inducer |
|
|
Repressible systems of regulation
|
In bacteria
In a constant state of transcription unless a corepressor is present to inhibit transcription |
|
|
Bacteriophage
|
A virus that infects its host bacterium by attaching to it, making a hle and injecting its DNA
|
|
|
Lytic Cycle
|
The phage DNA takes control of bacterium's genetic machinery. Bacterial cell bursts releasing new virions which can infect other bacteria.
|
|
|
Lysogenic Cycle
|
If bacteriophage doesn't lyse host cell, it becomes integrated into bacterial genome. Virus can stay integrated or the provirus can reemerge and enter lytic cycle
|
|
|
Where does fertilization occur?
|
the lateral, widest portion of the oviduct when the sperm encounters an egg
|
|
|
Cleavage in embryonic development
|
A series of rapid mitotic divisions which lead to an increase in cell number creating progressively smaller cells.
|
|
|
Indeterminate vs. Determinate cleavage
|
Indeterminant- results in cells that maintain the ability to develop into a complete organism
Determinate- results in cells whose future differentiation pathways are determined at an early developmental stage |
|
|
Morula
|
Solid ball of embryonic cells that forms through cleavage
|
|
|
Blastulation
|
Morula develops fluid-filled cavity called blasteocoel which becomes a hollow sphere of cells called the blastula
|
|
|
Ectoderm
|
Integuement
|
|
|
Endoderm
|
Epithelial lining of digestive/respiratory tracts
|
|
|
Mesoderm
|
Musculoskeletal system, circulatory system, excretory system, gonads and connective tissue and parts of digestive/respiratory organs
|
|
|
Chorion
|
Lines inside of egg shell. moist membrane that permits gas exchange
Egg membrane |
|
|
Allantois
|
Egg membrane
Sac-like structure involved in respiration and excretion |
|
|
Amnion
|
Egg membrane
Encloses amniotic fluid |
|
|
Yolk Ssac
|
Egg membrane
Encloses yolk. Blood vessels in yolk sac transfer food to the developing embryo |
|
|
marsupials develop in the mother without a
|
placenta
|
|
|
Circulation in protozoans happens by
|
Simple diffusion within the cell
|
|
|
Circulation in cnidarians happens by
|
Simple diffusion- body walls are two cells thick
|
|
|
Circulation in Arthropods happens by
|
Open circulatory system
|
|
|
In an open circulatory system
|
Blood is in direct contact with the body tissues and is circulated by body movements.
|
|
|
Blood flow in open circulatory system is
|
through dorsal vessel into sinuses
|
|
|
Circulation in annelids happens by
|
a closed circulatory system
|
|
|
How does a closed circulatory system work?
|
Blood is confined to blood vessels and moves towards the head in the dorsal vessel which functions as the main heart by coordinated contractions. Five aortic loops connect the dorsal vessel to the ventral vessel and act as additional pumps
|
|
|
Aortic loops
|
five pairs of vessels found in closed circulatory systems that connect the dorsal vessel tot he ventral vessel and function as pumps
|
|
|
Annelids are (what animal?)
|
earthworms
|
|
|
Human cardiovascular system is composed of
|
muscular four-chambered heart, a network of blood vessels and blood.
|
|
|
In the human cardiovascular system, blood is pumped into
|
the aorta
|
|
|
In the human cardiovascular system, blood is pumped from the aorta to
|
a series of arteries
|
|
|
Blood goes from the arteries
|
to arteriole
|
|
|
Blood goes from arterioles to
|
microscopic capillaries
|
|
|
Where does exchange of gases, nutrients and cellular waste products (through diffusion) take place in the human circulatory system?
|
In the capillaries
|
|
|
Blood goes from the capillaries to
|
the venules
|
|
|
blood goes from the venules
|
to the veins
|
|
|
blood goes from the veins
|
to the heart
|
|
|
Blood travelling in the veins is different than blood travelling through the arteries because it is
|
deoxygenated
|
|
|
The right side of the heart pumps _________ blood into _________ circulation
|
deoxygenated
pulmonary |
|
|
The left side fo the heart pumps __________ blood into _________ circulation
|
oxygenated
systemic |
|
|
Pulmonary circulation is
|
twoard the lungs
|
|
|
Systemic circulation is
|
throughout the body
|
|
|
The two upper chambers of the heart are called
|
atria
|
|
|
The two lower chambers of the heart are called
|
ventricles
|
|
|
What are the three types of blood vessels?
|
Arteries
Veins capillaries |
|
|
Arteries are
|
Thick walled, muscular
Transfer deoxygenated blood away from the heart |
|
|
Which arteries DO NOT transer deoxygenated blood away from the heart?
|
Pulmonary arteries- transfer deoxygenated blood from the heart to the lungs
|
|
|
Veins are
|
thin walled, inelastic
Conduct deoxygenated blood towards the heart |
|
|
Which veins don't transfer blood toward the heart?
|
Pulmonary veins transfer oxygenated blood from the lungs to the heart
|
|
|
Capillaries have
|
smallest diameter of three types of blood vessels and red blood cells travel through in single file
|
|
|
lymphatic System
|
Secondary circulatory system distinct from cardiovascular circulation
|
|
|
Lymphatic System transfers
|
interstitial fluid (lymph) to the cardiovascular system keeping fluid levels in the body constant
|
|
|
lymph nodes (function)
|
Contain phagocytic cells that filter the lymph and remove/destroy foreign particles
|
|
|
Composition of blood
|
55% liquid
45% cellular componenets |
|
|
Plasma is
|
the liquid portion of the blood
|
|
|
Erythrocytes
|
Red blood cells
Each one can bind to up to four molecules of oxygen. Formed from stem cells in bone marrow |
|
|
Oxyhemoglobin
|
Hemoglobin bound to oxygen
|
|
|
Leukocytes
|
White blood cells
Larger than erythrocytes Protective functions |
|
|
Macrophages
|
Stationary leukocytes that have migrated from blood to tissue.
|
|
|
Lymphocytes
|
Lymphocytes that are involved in immune response and the production of antibodies
|
|
|
Platelets
|
Cell fragments (no nuclei)
Form clots- injury repair |
|
|
Leukocytes are the main component of
|
the immune system
|
|
|
Hemoglobin binds to both
|
O2 and CO2
|
|
|
Where are amino acids and simple sugars absorbed into the bloodstream?
|
Intestinal capillaries
|
|
|
Where do metabolic waste products enter the blood stream?
|
Through capillaries throughout the body
|
|
|
How does clotting happen?
|
Platelets release a chemical to allow platelet plug formation
Thromboplastin is released- converts inactive protein prothrombin into thrombin Thrombin converts firinogen into fibrin Fibrin threads coat damaged area trapping blood cells to form a clot. |
|
|
Humoral Immunity
|
Defense mechanism that involves the production of antibodies specific to the antigen involved.
|
|
|
Cell-mediated Immunity
|
Defense mechanism.
Involves cells that combat fungal and viral infection |
|
|
Humoral and cell-mediated immunity is conducted by
|
Lymphocytes
|
|
|
Antibodies/Immunoglobulins
|
Complex proteins that recognize and bind to specific antigens triggering removal by immune system
|
|
|
What are the two ways that antibodies deal with antigens?
|
Attract other cells (like leukocytes) to phagocytize the antigen
Cause antigens to clump together and form large insoluble complexes, facilitating removal by phagocytic cells |
|
|
Active Immunity
|
Production of antibodies during immune response. Can be conferred by vaccination
|
|
|
Vaccination
|
Injection of a weakened form of an antigen that stimulates the immune system to produce antibodies
|
|
|
Passive Immunity
|
Transfer of antibodies produced by another individual or organism. Acquired passivley or by injection
|
|
|
Gamma globulin
|
Uses passive immunity to confer temporary protection against hepatitis
|
|
|
Five nonspecific defense mechanisms of human body?
|
Skin
Mucous-coated epithelia lined passages Macrophages Inflammatory response Interferons |
|
|
Mucous coated epithelia
|
Nonspecific defense mechanism of body.
Lines passages in body and filters/traps foreign particles |
|
|
Macrophages
|
Engulf and destroy foreign particles
Nonspecific defense mechanism of body |
|
|
Inflammatory Response
|
Nonspecific defense mechanism of body
Injured cells release histamine making blood vessels dilate increasing blood flow to damaged region. Granulocytes phagocytize antigenic material. |
|
|
Interferons
|
Nonspecific defense mechanism of human body
Produced when cell is under viral attack Diffuse to other cells preventing spread of the virus |
|
|
Allergic REaction
|
Inappropriate responses to certain foods/pollen causing body to form antibodies and release histamine.
|
|
|
How does the body accept transplants?
|
Immuno-suppressing drugs can be used do decrease likelihood of rejection
|
|
|
What are the two groups of red blood cell antigens?
|
ABO group and the Rh factor
|
|
|
Type AB blood is
|
universal recipient
|
|
|
Type O blood is
|
Universal donor
|
|
|
Erythroblastosis Fetalis
|
When a fetus has severe anemia
When an Rh- woman carries an Rh+ fetus and the anti-Rh antibodies destroy fetal red blood cells |
|
|
Translocation
|
Circulation in plants
|
|
|
What is the primary organ of transport in the plant?
|
The plant stem
|
|
|
Vascular bundles
|
Found in plant stems
Contain xylem, phloem and cambium cells |
|
|
Xylem cells are
|
Thick-walled, often hollow
Located on the inside of the vascular bundle. Carry water and minerals up the plant |
|
|
What are the two types of xylem cells?
|
Vessel cells
Tracheids |
|
|
How does water rise in the xylem?
|
transpiration pull, capillary action and root pressure
|
|
|
Transpiration Pull
|
as water evaporates from the leaves of plants, a vacuum is created which pulls water up the stem
|
|
|
Capillary Action
|
Any liquid in a thin tube rises due to surface tension of liquid
|
|
|
Root Pressure
|
Water entering root hairs pushes water up stem
|
|
|
Phloem Cells
|
Thin-walled cells on outside of vascular bundle
Transport nutrients down the stem |
|
|
Sieve tube cells and companion cells are part of
|
Phloem cells in plants
|
|
|
Cambium Cells
|
Two layers thick.
Actively dividing and undifferentiated cells that give rise to xylem and phloem Found between xylem and phloem cells in plant stem |
|
|
Structure of stem from outside to inside
|
Epidermis
Cortex Phloem Cambium Xylem Pith |
|
|
Fibrovascular Bundle
|
In plant stem
Phloem, cambium and xylem layers |
|
|
What is the role of a plant root?
|
Absorbs material through root hairs and anchors the plant.
Store energy |
|
|
Root hairs
|
Specialized cells of root epidermis- increase surface area for water absorption
|
|
|
Layers of the root?
|
Same as layers of the stem:
Epidermis Cortex Phloem Xylem Cambium |
|
|
Meristem
|
Actively dividing, undifferentiated cells of the plant
|
|
|
Cambium
|
Found between phloem and xylem. A type of meristem- lateral meristem providing lateral growth of stem by adding to phloem or xylem.
|
|
|
Apical Meristem
|
At the tips of roots and stems. Division leads to increase in length, elongating new cells which differentiate into specialized cell of plant
|
|
|
Hormones
|
Synthesized and secreted by endocrine glands into the circulatory system.
|
|
|
What determines the specificity of hormonal action?
|
The presence of specific receptors on or in target cells.
|
|
|
Adrenal Glands- location and components
|
Top of kidneys
Consist of adrenal cortex and adrenal medulla |
|
|
ACTH- What does it do? Where does it come from?
|
Produced by anterior pituitary
Stimulates adrenal cortex to synthesize/secrete steroid hormones |
|
|
Corticosteroids- What are they?
|
Collective name for steroid hormones
|
|
|
Glucocorticoids- What do they do? Examples
|
Glucose regulation and protein metabolism
Cortisol and cortisone |
|
|
Glucocorticoids raise blood glucose levels by
|
promoting protein breakdown and gluconeogenesis and decreasing protein synthesis
|
|
|
Mineralocorticoids- what do they do?
|
Regulate plasma levels of sodium and potassium= regulate total extracellular water volume
|
|
|
How does aldosterone control both blood volume and blood pressure?
|
It can cause active reabsorption of sodium and passive reabsorption of water causing both blood volume and blood pressure to rise
|
|
|
What happens when there is excess production of aldosterone?
|
Excess retention of water which in turn causes hypertension (high blood pressure)
|
|
|
Androgens- What? From where?
|
Male sex hormones secreted by adrenal cortex. Produced by testes
|
|
|
What happens when there is overproduction of adrenal androgens in females?
|
Maculinizing effects- like facial hair
|
|
|
Epinephrine- what? from where?
|
Adrenaline. Produced by adrenal medulla.
|
|
|
Norepinephrine- what? from where?
|
Noradrenaline produced by adrenal medulla
|
|
|
Catecholamines- what? examples
|
Class of amino-acid derived compounds
Epinephrine and norepinephrine- both produced by adrenal medulla |
|
|
What do epinephrine and norepinephrine do to effect blood flow in the body? What is this called?
|
They increase the rate and strength of the heartbeat and dilate and constrict blood vessels to increase blood supply to skeletal muscle, the heart, the brain and decrease blood supply to the kidneys, skin and digestive tract.
Fight or flight response |
|
|
What stimulus releases epinephrine?
|
Stress
|
|
|
ACTH- what? what does it do? where does it come from?
|
Adrenocorticotrophic hormone secreted by the anterior pituitary gland. Stimulates production of glucocorticoids and sex steroids
|
|
|
Pituitary gland- structure and location
|
Small, tri-lobed gland near base of brain
|
|
|
Hyphophysis gland is?
|
Pituitary gland
|
|
|
Anterior Pituitary- what does it do?
|
Synthesizes direct hormones and tropic hormones
|
|
|
What regulates the secretions of the anterior pituitary gland?
|
Hypothalamic secretions called releasing/inhibiting hormones or factors
|
|
|
Tropic Hormones- What do they do? Where
|
Stimulate other endocrine glands to release hormones.
Found in anterior pituitary |
|
|
Direct Hormones- what do they do? Where?
|
Stimulate their target organs directly
Found in anterior pituitary |
|
|
Growth Hormones- What do they do? Where?
|
Promote bone and muscle growth. Direct hormone found in anterior pituitary
|
|
|
Prolactin- What does it do? Where?
|
Stimulates milk production and secretion in female mammary glands.
Direct hormone found in anterior pituitary |
|
|
What causes dwarfism?
|
Growth hormone deficiency in children causing stunted growth.
|
|
|
Gigantism- cause?
|
Overproduction of growth hormones in children
|
|
|
What causes acromegaly?
|
Overproduction of growth hormones in adults
|
|
|
Endorphines- What does it do? Where?
|
Inhibit perception of pain
Direct hormones produced by anterior pituitary |
|
|
Andrenocorticotropic Hormone (ACTH)- What does it do? Where?
|
Stimulates adrenal cortex to synthesize and secrete glucocorticoids. Regulated by corticotrophic releasing factor
Tropic hormone produced by anterior pituitary |
|
|
Thyroid-stimulating Hormone- What does it do? Where?
|
Stimulates the thyroid gland to synthesize and realize thyroid hormone
Tropic hormone produced by anterior pituitary. |
|
|
Luteinizing Hormone- What does it do? Where?
|
Stimulates ovulation and formation of the corpus luteum in females.
Stimulates interstitial cells of the testes to synthesize testosterone in males Tropic hormone produced by anterior pituitary |
|
|
Follicle Stimulating Hormone
|
Causes maturation of ovarian follicles causing estrogen secretion in females
Stimulates maturation of seminiferous tubules in males Tropic hormone produced by anterior pituitary |
|
|
Melanocyte-Stimulating Hormone- What does it do? Where?
|
Secreted by intermediate lobe of pituitary. In frogs it causes darkening of skin
Tropic hormone produced by anterior pituitary |
|
|
Neurohypophysis
|
Posterior pituitary gland
|
|
|
What does the posterior pituitary gland do?
|
tores and releases peptide hormones oxytocin and ADH
|
|
|
What produces oxytocin and ADH
|
Neurosecretory cells and the hypothalamus
|
|
|
Oxytocin- What does it do? How?
|
Increases strength and frequency of uterine muscle contractions.
Induced by suckling- stimulates milk secretion in mammary glands. |
|
|
Antidiuretic Hormone- What does it do? When is it secreted?
|
ADH
Increases permeability of nephron's collecting duct promoting water reabsorption and increasing blood volume Secreted when plasma osmolarity increases or when blood volume decreases |
|
|
Hypothalamus- location
|
Part of forebrain located directly above pituitary gland
|
|
|
What does the hypothalamus do?
|
Receives neural transmissions from other parts of the brain and from peripheral nerves that trigger specific responses from its neurosecretory cells.
|
|
|
How do neurosecretory cells regulate the pituitary gland?
|
Via negative feed back mechanisms and through inhibiting and releasing hormones
|
|
|
What are hypothalamic releasing hormones?
|
Hormones that stimulate or inhibit the secretions of the anterior pituitary
|
|
|
GnRH- What is it?
|
Stimulates anterior pituitary to secrete FSH and LH
Hypothalamic releasing hormone |
|
|
Path of hypothalamic releasing hormones
|
Releasing hormones are secreted into the hypothalamic-hypophyseal portal system where bloo fromt he capillary bed in the hypothalamus flows through a portal vein into the anterior pituitiary where it diverges into a second capillary network. This allows releasing hormones to immediately reach the anterior pituitary
|
|
|
How does the hypothalamus interact with the posterior pituitary?
|
Neurosecretory cells in hypothalamus synthesize oxytocin and ADH and transport them into posterior pituitary for storage and secretion
|
|
|
Thyroid Gland- Structure and Location
|
Located on ventral surface of trachea
|
|
|
What does the thyroid gland do?
|
Produces and secretes thyroxin, triidothyronine and calcitonin
|
|
|
Thyroxine and Triidothyronine- What does it do?
|
Derived from amino acid tyrosine
Necessary for growth and neorological development in children Increase rate of metabolism throughout body |
|
|
Hypothyroidism- Cause? Symptoms?
|
Thyroid hormones are undersecreted
Slowed heart rate and respiratory rate, fatigue, cold intolerance and weight gain |
|
|
Cretinism
|
Hypothyroidism in newborns causes mental retardation and short stature
|
|
|
Hyperthyroidism
|
Thyroid is overstimulated resulting in oversecretion of thyroid hormones causes increased metabolic rate
|
|
|
Calcitonin
|
Decreases plasma Ca2+ concentration by inhibiting its release from the bone.
Regulated by plasma Ca2+ levels |
|
|
Pancreas- what is it?
|
Both an exocrine organ and an endocrine organ
|
|
|
What is the exocrine function of the pancreas?
|
Performed by cells that secrete digestive enzymes into small intestine via ducts
|
|
|
What is the endocrine function of the pancreas?
|
Performed by small glandular structures called the islets of Langerhans
|
|
|
Islets of Langerhans
|
Part of endocrine function of pancreas.
Composed of alpha and beta cells |
|
|
What do alpha cells do (in islets of Langerhans)?
|
Produce and secrete glucagon
|
|
|
What do beta cells do (in islets of Langerhans)?
|
Produe and secrete insulin
|
|
|
Glucagon- what does it do?
|
Stimulates protein and fat degradation, conversion of glycogen to glucose and gluconeogenesis which all increase blood glucose levels.
|
|
|
Insulin- what does it do?
|
Protein hormone that's secreted in response to a high blood glucose concentration
|
|
|
How does insulin work?
|
Stimulates the uptake of glucose by muscle and adipose cells and the storage of glucose as glycogen in muscle and liver cells.
Stimulates synthesis of fats from glucose and the uptake of amino acids |
|
|
Diabetes Mellitus
|
Underproduction of insulin causing hyperglycemia
|
|
|
Parathyroid Glands- structure
|
Four small pea-shaped structures in the posterior surface of the thyroid.
|
|
|
What do the parathyroid glands do?
|
Synthesize and secrete parathyroid hormone which regulates plasma Ca2+ concentration
|
|
|
How does PTH ragulate plasma Ca2+ concentrations?
|
Stimulates Ca2+ release from bone and decreases Ca2+ excretion in kidneys
|
|
|
Kidneys- function
|
Produce renin when blood volume falls
|
|
|
What does renin do?
|
Enzyme that converts plasma protein angiotensinogen to angiotensin I which is converted to antiogensin II which stimulates adrenal cortex to secrete aldosterone.
|
|
|
What does aldosterone do?
|
Helps restore blood volume by increasing sodium reabsorption at the kidney leading to an increase in water removing initial stimulus for renin production
|
|
|
Gastrin
|
Hormone that is released when food is ingested. After realease it is carried to gastric glands where it stimulates the glands to secrete HCl in response to food in the stomach.
|
|
|
Secretin
|
Hormone that is released by small intestine when acidic food material enters the stomach. Stimultes secretion of solution that neutralizes the acidity of the chyme (partially digested food)
|
|
|
Cholecystokinin
|
Hormone released by small intestine in response to presence of fats that causes gall bladder contraction and release of bile
|
|
|
Bile
|
Involved in fat digestion
|
|
|
Pineal Gland
|
Structure at base of brain that secretes melatonin which plays a role in circadian rhythms
S |
|
|
Melatonin secretion is regulated by
|
light and dark cycles
|
|
|
What are teh two major groups of hormones?
|
Peptide
Steroid |
|
|
How do hormones effect the activities of their target cells?
|
Extracellular receptors
Intracellular receptors |
|
|
Peptide Hormones
|
Act as first messengers that bind to specific receptors on the surface of their target cells triggering enzymatic reactions in each cell.
|
|
|
Cyclic AMP
|
Relays messages from extracellular peptide hormone to cytoplasmic enzymes initiating reactions inc ell
|
|
|
Seroid Hormones
|
Produced by testes, ovaries, placenta and adrenal cortex.
Lipid soluble- enter target cells directly and bind to specific receptor proteins in cytoplams. Receptor hormone complex enters nucleus and activates expression of specific genes by binding to receptors on chromatin inducing a change in mRNA transcription |
|
|
What produces plant hormones?
|
ACtively growing parts of the plant like the meristematic tissues in the apical region
|
|
|
Phototropism
|
Tendency of shoots of plants to bend toward light source. Controlled by auxins.
|
|
|
Indoleacetic acid
|
One of the auxins associated with phototrophism
|
|
|
Geotropism
|
Growth of portions of plants away or towards gravity
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Negative Geotropism
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Causes shoots to grow upward and away from acceleration of gravity
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Positive Geotropism
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Causes roots to grow towards the pull of gravity
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Auxin inhibition of lateral buds
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Auxins produced in terminal bud of a plant's growing tip move downward in the shoot and inhibit development of later bud
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Gibberellins
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Stimulate rapid stem elongation particularly inplants that don't grow tall.
Inhibit formation of new roots and stimulate production of new phloem cells by cambium Terminate dormancy of seeds and buds |
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Kinins
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Promote cell division
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Ratio of kinetin to auxin
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determines timing of differentiation of new cells
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Ethylene
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Stimulates fruit ripening and induces aging in plants
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Inhibitors
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Block cell division- growth regulation. Important to maintenance of dormancy in lateral buds and seeds of plants
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Abscisic acid
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One of the most important inhibitors in plants
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Anti-Auxins
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Regulate activity of auxins
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Indoleacetic Acid concentration regulation
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Controlled by indoleacetic acid oxidase. Increase in idoleacetic acid increases amoutn of indoleacetic acid oxidase produced.
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Nervous System- role
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Allows organism to receive and respond to stimuli from external and internal environments
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Neurons
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Functional units of nervous system
Convert stimuli into electrochemical signals that are conducted through the nervous system |
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Structure of a neuron
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Elongated cell made of several dendrites, a cell body and an axon.
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Dendrites
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Cytoplasmic extensions that receive information and transmit it toward the cell body.
Part of the neuron |
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Axon
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Part of neuron
Long cellular process that transmits impulses away from cell body |
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Myelin
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Substance that sheaths most mammalian axons
Allows axons to conduct impulses faster Produced by glial cells |
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What produces myelin?
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Oligodendrocytes and Schwann cells
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Nodes of Ranvier
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Gaps between segments of yelin
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Neurotransmitters
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Are released from synaptic terminals on axons into synapse
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Synapse
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Gap between axon terminals of one cell and the dendrites of the next cell
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Neuron- Function
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Receive signals from sensory receptors or other neurons and transfer information along length of axon
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Action Potentials
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Impulses that travel through neurons and invade the nerve terminal causing neurotransmitter release
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Resting Potential
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Potential difference between the extracellular space and intracellular space when neuron is at rest due to unequal distribution of ions.
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A typical resting membrane potential is
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-70 millivolts- inside of neuron is more negative
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Why is the inside of a neuron more negative?
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Na+/K+ pump makes K+ concentration higher inside the neuron. K+ diffuses down concentration gradient leaving a net negative charge inisde
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How is the concentration gradient in the neuron restored?
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Na+/K+ pump transports three Na+ out for every two K+ transported into cell
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Action Potential
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Generated when neuron becomes sufficiently excited or depolarized and the inside becomes more negative. In response to depolarization, voltage gated Na+ channels are opened depolarizng a segment of the cell and then close. Voltage-gated K+ channels open allowing K+ to rush out down its electrochemical gradient- repolarization= making cell more negative. Cell enters refractory period right after because it is difficult for it to initiate another action potential
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All-or-none Response
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When the threshold membrane potential of a neuron is reached, an action potential with a cosnistent size and duration is produced
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What direction does information transfer occur in?
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From dendrite to synaptic terminal
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The greater the diamter of an axon,
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the faster the impulses travel
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Synapse
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Gap between the axon terminal of one neuron (the presynaptic neuron) and the dendrites of another neuron (postsynaptic neuron)
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Effector Cells
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Cells other than neurons that neurons communicate with like muscles or glands
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Neurotransmitters
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Membrane-bound vesicles full of chemical messengers
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Curare
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Blocks post-synaptic acetylcholine receptors so that acetylcholine is unable to interact with the receptor leading to paralysis
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Botulism Toxin
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Prevents release of acetylcholine from presynaptic membrane- results in paralysis
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Anti-cholinesterases
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Inhibit activity of acetylcholinesterase enzyme. Prevents coordinated muscular contractions from taking place
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Protozoa- Nervous system?
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No organized nervous system
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Cnidaria
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Simple nervous system called nerve net
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Annelida- Nervous system?
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Central nervous system consisting of devined ventral nerve cord, anterior brain of fused ganglia adn definitive nerve pathways from receptors to effectors
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Arthropoda- Nervous system?
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Similar brains to those of annelids but more specialized sense organs
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Afferent Neurons
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Carry sensory information
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Efferent Neurons
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Carry motor commands
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Interneurons
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Participate only in local circuits linking sensory and motor neurons in brain and spinal cord
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Plexus
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Network of nerve fibers
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Ganglia
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Neuronal cell body clusters
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Central nervous system consists of
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brain and spinal cord
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Brain functions
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Interpreting sensory information
Forming motor plans Cognitive function |
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Brain structure
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Outer portion called gray matter
Inner white matter |
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Components of forebrain
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TelencephalonDiencephalon
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Cerebral cortex
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Major component of telencephalon
Highly convoluted gray matter Can be seen on surface of brain |
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Olfactory Bulb
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Center for reception and integration of olfactory input
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Diencephalon
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Thalamus and hypothalamus
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Thalamus
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Relay and integration center for spinal cord and cerebral cortex
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Hypothalamus
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Controls visceral functions like hunger, thirst, sex drive, water balance, blood pressure, temperature regulation
Controls endocrine system |
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Midbrain
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Relay center for visual and auditory impulses
Plays role in motor control |
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Mesencephalon
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Midbrain
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Hindbrain
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Posterior part of brain. Consists of cerebellum, pons and medulla
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Cerebellum
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Modulates motor impulses initiated by cerebral cortex. Important in maintaining balance, hand-eye coordination and timing of rapid movements
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Pons
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relay center to allow cortex to communicate with cerebellum
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Medulla
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Controls vital functions like breathing, heart rate, gatrointestinal activity
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Brainstem
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Midbrain
pons Medulla |
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Spinal Cord
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Conduit for sensory information to brain and motor information from brain
Integates reflexes by itself Consists of outer white matter area of motor and sensory axons and inner gray matter area containing nerve cell bodies |
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Dorsal Horn
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Sensory info. enters spinal cord from here
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Ventral Horn
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All motor information exits spianl cord from here
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Peripheral Nervous System
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Consists of nerves and ganglia, sensory nerves that enter CNS and motor nerves that leave CNS
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Somatic Nervous System
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Innervates skeletal muscles and is responsible for voluntary movement
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Autonomic Nervous System
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Regulates body's internal environment without conscious control
Innervates cardiac and smooth muscle. Important in blood pressure control, gastrointestinal motility, excretory processes, respiration and reproductive processes |
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Sympathetic Nervous System
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Responsible for fight or flight responses. Increases blood pressure and heart rate. Increases blood flow to skeletal muslces and decreases gut motility. Dilates bronchiles to increase gas exchange. Uses norepinephrine as primary transmitter
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Parasympathetic Nervous System
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Acts to conserve energy and restore body to resting activity levels following exertion. Lowers heart rate, increases gut motility
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Vagus Nerve
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Importan nerve of parasympathetic nervous system.
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Myopia
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Nearsightedness
Image is focused on front of retina |
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Hyperopia
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Farsightedness
Image is focused behind retina |
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Astigmatism
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Caused by irregularly shaped cornea
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Cataracts
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Develp when lens becomes opaque and light cannot enter- blindnes
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Glaucoma
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Increase in pressure in eye due to blocking of outflow of aqueous humor
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External Respiration
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Entrance of air into lungs and gas exchange between alveoli and blood
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Internal Respiration
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Exchange of gas between blood and cells and intracellular processes of respiration
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Dehydrogenation
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High energy H atoms are removed from organic molecules during respiration
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Glycolysis
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First stage of glucose catabolism. Series of reactions that lead to oxidative breakdown of glucose into two pyruvate molecules, ATP, reduction of NAD+ into NADH
Takes place in cytoplasm |
