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15 Cards in this Set
- Front
- Back
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The components of cell theory. |
A cell is the basic structural and functional unit of living organisms. •The activity of an organism depends on the collective activities of its cells. •According to the principle of complementarity, the biochemical activities of cells are dictated by the relative number of their specific subcellular structures. •Continuity of life has a cellular basis. |
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List the three major regions of a generalized cell and indicate the general function of each region. |
The Nucleus •Control center of the cell Plasma Membrane •Barrier for cell contents Cytoplasm •The material outside the nucleus and inside the plasma membrane |
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Distinguish between intracellular fluid and extracellular fluid. |
Intracellular fluid is the liquid located inside the cells, while extracellular fluid surrounds the cells. While intracellular fluid contains proteins and amino acids and has a concentration gradient, extracellular fluid presents with more ions. With that being said, while both fluids contain glucose, only intracellular fluid is able to convert it into energy due to the function of its organelles. |
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Describe the three types of cell membrane junctions and note their locations. |
Tight junctions •Impermeable junctions •Bind cells together into leak proof sheets Desmosomes •Anchoring junctions that prevent cells from being pulled apart •Gap junctions •Allow communication between cells |
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Discuss the structure and function of the mitochondria ribosomes, endoplasmic reticulum (rough & smooth), and the golgi apparatus, lysosomes, peroxisomes, cytoskeleton, centrioles; note the functional interrelationships among the organelles. |
Mitochondria •“Powerhouses”of the cell •Change shape continuously •Carry out reactions where oxygenis used to break down food •Provides ATP for cellular energy Ribosomes •Made of protein and RNA •Sites of protein synthesis •Found at two locations •Free in the cytoplasm •As part of the rough endoplasmic reticulum Endoplasmic reticulum (ER) •Fluid-filled tubules for carrying substances •Two types of ER •Rough endoplasmic reticulum •Studded with ribosomes •Synthesizes proteins •Smooth endoplasmic reticulum •Functions in lipid metabolism and detoxification of drugs and pesticides Golgi apparatus •Modifies and packages proteins •Produces different types of packages •Secretory vesicles •Cell membrane components Lysosomes •Contain enzymes produced by ribosomes •Packaged by the Golgi apparatus •Cell’s demolition site/waste disposalsystem/suicide bags •Digest worn-out or non-usable materials within the cell including protein, lipids, cell debris •Digest foreign substances such as microorganisms Peroxisomes •Membranous sacs of oxidase enzymes •Detoxify harmful substances such as alcohol and formaldehyde •Break down free radicals (highly reactive chemicals) Cytoskeleton •Network of protein structures that extend throughout the cytoplasm •Provides the cell with an internal framework •Three different types of elements •Microfilaments (smallest) •Intermediate filaments •Microtubules (largest) Centrioles •Rod-shaped bodies made of microtubules •Direct the formation of mitotic spindle during cell division |
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What are cell extensions. |
Cilia move materials across the cell surface •Made of microtubules •Located in the respiratory system to move mucus Flagella propel the cell •Made of microtubules •The only flagellated cell in the human body is sperm Microvilli are tiny, finger like extensions of the plasma membrane •Made of actin filaments •Increase surface area for absorption |
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Relate plasma membrane structure to active and passive transport mechanisms. Differentiate clearly between these transport processes relative to energy source, substances transported, and direction of transport. |
Membrane transport—movement of substances into and out of the cell •Cell membranes are selectively permeable •Two basic methods of transport Passive processes •No energy is required Active processes •Cell must provide metabolic energy (ATP) Passive Processes Types of diffusion •Simple diffusion •An unassisted process •Solutes are lipid-soluble materials or small enough to pass through membrane pores Types of diffusion (continued) •Osmosis—simple diffusion of water •Highly polar water molecules easily cross the plasma membrane through aquaporins Facilitated diffusion •Substances require a protein carrier for passive transport •Transports lipid-insoluble and large substances (too large to pass through the pores) Filtration •Water and solutes are forced through a membrane by fluid, or hydrostatic pressure •A pressure gradient must exist •Solute-containing fluid is pushed from a high-pressure area to a lower pressure area Active Processes Substances are transported that are unable to pass by diffusion •Substances may be too large •Substances may not be able to dissolve in the fat core of the membrane •Substances may have to move against a concentration gradient •ATP is used for transport Two common forms of active transport Active transport (solute pumping) • Amino acids, some sugars, and ions are transported by protein carriers called solute pumps • ATP energizes protein carriers• In most cases, substances are moved against concentration gradients Vesicular transport •Exocytosis •Moves materials out of the cell •Material is carried in a membranous vesicle •Vesicle migrates to plasma membrane •Vesicle combines with plasma membrane •Material is emptied to the outside Vesicular transport •Exocytosis •Endocytosis •Phagocytosis •Pinocytosis Vesicular transport (continued) •Endocytosis •Extracellular substances are engulfed by being enclosed in a membranous vescicle •Types of endocytosis •Phagocytosis—“cell eating” •Pinocytosis—“cell drinking” |
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List the phases of the cell life cycle and describe the events of each phase. |
Cells have two major periods Interphase •Cell grows •Cell carries on metabolic processes Cell division •Cell replicates itself •Function is to produce more cells for growth and repair processes Prophase •First part of cell division •Centrioles migrate to the poles to direct assembly of mitotic spindle fibers •DNA appears as double-stranded chromosomes •Nuclear envelope breaks down and disappears Metaphase •Chromosomes are aligned in the center of the cell on the metaphase plate Anaphase •Chromosomes are pulled apart and toward the opposite ends of the cell •Cell begins to elongate Telophase •Chromosomes uncoil to become chromatin •Nuclear envelope reforms around chromatin •Spindles break down and disappear Late prophase Cytokinesis •Begins during late anaphase and completes during telophase •A cleavage furrow forms to pinch the cells into two parts |
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Describe the process of DNA replication. Explain the importance of this process. |
Genetic material is duplicated and readies a cell for division into two cells •Occurs toward the end of interphase •DNA uncoils and each side serves as a template |
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Describe process of protein synthesis- role of RNA, terms transcription and translation. |
Protein Synthesis •Gene—DNA segment that carries a blueprint for building one protein Proteins have many functions •Building materials for cells •Act as enzymes (biological catalysts) •RNA is essential for protein synthesis Role of RNA •Transfer RNA (tRNA) •Transfers appropriate amino acids to the ribosome for building the protein •Ribosomal RNA (rRNA) •Helps form the ribosomes where proteins are built •Messenger RNA (mRNA) •Carries the instructions for building a protein from the nucleus to the ribosome Transcription and Translation Transcription •Transfer of information from DNA’s base sequence to the complimentary base sequence of mRNA •Three-base sequences on mRNA are called codons Translation •Base sequence of nucleic acid is translated to an amino acid sequence •Amino acids are the building blocks of proteins |
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Name the four primary tissue types of the body and give their locations. Explain how these four tissue types differ structurally and functionally. |
Four primary types •Epithelial tissue (epithelium) •Connective tissue •Muscle tissue •Nervous tissue Epithelial Tissues Locations •Body coverings •Body linings •Glandular tissue Functions •Protection •Absorption •Filtration •Secretion Connective Tissue •Found everywhere in the body •Includes the most abundant and widely distributed tissues Functions •Binds body tissues together •Supports the body •Provides protection Muscle Tissue Function is to produce movement Three types •Skeletal muscle •Cardiac muscle •Smooth muscle Nervous Tissue •Composed of neurons and nerve support cells Function is to send impulses to other areas of the body •Irritability •Conductivity •Support cells called neuroglia insulate, protect,and support neurons |
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Classification of epithelial tissue. Give examples of where each is located and the function of each type. Explain the structure of each type. |
Shape of cells Squamous •flattened Cuboidal •cube-shaped Columnar •column-like Simple cuboidal •Single layer of cube-like cells Locations •Common in glands and their ducts •Forms walls of kidney tubules •Covers the ovaries •Functions in secretion and absorption; ciliated types propel mucus or reproductive cells Simple columnar •Single layer of tall cells• Often includes mucus-producing goblet cells Location - lines digestive tract Functions in secretion and absorption; ciliated types propel mucus or reproductive cells Pseudostratified columnar •Single layer, but some cells are shorter than others •Often looks like a double layer of cells but all cells rest on the basement membrane •Location - respiratory tract, where it is ciliated •Functions in absorption or secretion Stratified squamous •Cells at the apical surface are flattened Functions as a protective covering where friction is common Locations - lining of the: •Skin •Mouth •Esophagus Stratified cuboidal—two layers of cuboidal cells; functions in protection •Stratified columnar—surface cells are columnar, cells underneath vary in size and shape; functions in protection •Stratified cuboidal and columnar •Rare in human body •Found mainly in ducts of large glands Transitional epithelium •Composed of modified stratified squamous epithelium •Shape of cells depends upon the amount of stretching •Functions in stretching and the ability to return to normal shape •Location - lines organs of the urinary system Gland •One or more cells responsible for secreting a particular product •Secretions contain protein molecules in an aqueous (water-based) fluid Glandular Epithelium Two major gland types •Endocrine gland •Ductless since secretions diffuse into blood vessels •Ex. hormones •Exocrine gland •Secretions empty through ducts to the epithelial surface •Include sweat and oil glands |
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Classification of connective tissue. Give examples of where each is located and the function of each type. Explain the structure of each type. |
Found everywhere in the body •Includes the most abundant and widely distributed tissues Functions •Binds body tissues together •Supports the body •Provides protection Extracellular Matrix •Two main elements •Ground substance—mostly water along with adhesion proteins and polysaccharide molecules •Fibers •Produced by the cells •Three types •Collagen (white) fibers •Elastic (yellow) fibers •Reticular fibers Bone (osseous tissue) •Composed of •Bone cells in lacunae (cavities) •Hard matrix of calcium salts •Large numbers of collagen fibers •Functions to protect and support the body Cartilage- Hyaline cartilage •Most common type of cartilage •Composed of •Abundant collagen fibers •Rubbery matrix •Locations •Larynx •fetal skeleton prior to birth •Functions as a more flexible skeletal element than bone Fibrocartilage •Highly compressible •Location •Forms cushion-like discs between vertebrae •Elastic cartilage •Provides elasticity Location •Supports the external ear Dense connective tissue (dense fibrous tissue) •Main matrix element is collagen fiber •Fibroblasts are cells that make fibers Locations •Tendons—attach skeletal muscle to bone •Ligaments—attach bone to bone at joints •Dermis—lower layers of the skin Loose connective tissue types •Areolar tissue •Most widely distributed connective tissue• Soft, pliable tissue like “cobwebs” Functions as a packing tissue •Contains all fiber types •Can soak up excess fluid (causes edema) Loose connective tissue types •Adipose tissue •Matrix is an areolar tissue in which fat cells predominate •Many cells contain large lipid deposits Functions •Insulates the body •Protects some organs •Serves as a site of fuel storage Loose connective tissue types •Reticular connective tissue •Delicate network of interwoven fibers Locations •Forms stroma (internal supporting network) of lymphoid organs •Lymph nodes •Spleen •Bone marrow Blood (vascular tissue) •Blood cells surrounded by fluid matrix called blood plasma •Fibers are visible during clotting •Functions as the transport vehicle for materials |
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Identify the three types of muscle tissue. Give examples of where each islocated and the function of each type. Explain the structure of each type. |
Function is to produce movement Three types: •Skeletal muscle •Cardiac muscle •Smooth muscle Skeletal muscle •Under voluntary control •Contracts to pull on bones or skin •Produces gross body movements or facial expressions •Characteristics of skeletal muscle cells •Striated •Multinucleate (more than one nucleus) •Long, cylindrical cells Cardiac muscle •Under involuntary control •Found only in the heart •Function is to pump blood •Characteristics of cardiac muscle cells •Striated •One nucleus per cell •Cells are attached to other cardiac muscle cells at intercalated disks Smooth muscle •Under involuntary muscle •Found in walls of hollow organs such as stomach, uterus, and blood vessels •Characteristics of smooth muscle cells •No visible striations •One nucleus per cell •Spindle-shaped cells |
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Describe the cells in nervous tissue. Identify the location and function of nervous tissue. |
Nervous Tissue •Composed of neurons and nerve support cells •Function is to send impulses to other areas of the body •Irritability •Conductivity •Support cells called neuroglia insulate, protect,and support neurons Brain, spinal chord. |
