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365 Cards in this Set
- Front
- Back
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Cylindrical organelles that
function in cell division |
Centrioles
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Organelle that produces, transports, and stores proteins
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Endoplasmic Reticulum (ER)
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The organelle that packages things that are going to be sent out of the cell and transports them to the cell membrane
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Gogli Apparatus
(Gogli Complex & Gogli Body) |
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A type of enzyme that breaks down destructive hydrogen peroxide into harmless water and oxygen
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Catalases
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Organelles that contain catalases
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Peroxisomes
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Organelles that produce ATP for cells
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Mitochondria
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Key features of mitochondria
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Double-membraned with lots of crests and dips in the inner membrane (increasing surface area)
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Part of a cell containing chromosomes (and thus DNA)
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Nucleus
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Organelle that produces ribosomes
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Nucleolus
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Abbreviation for ribosomes
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rRNA
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Intracellular circulation
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Cytoplasmic streaming
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Organelles containing digestive enzymes
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Lysosomes
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Enzymes that digest waste and ingested material
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Hydrolytic enzymes
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Sites of protein synthesis in a cell
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Ribosomes
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What centrioles are made of
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Microtubules
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Empty space in a cell surrounded by a membrane, sometimes serving as storage
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Vacuoles
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What an atom contains
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Nucleus (with a neutron and proton)
plus electrons |
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Element involved in pH measurements
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Hydrogen
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What pH evaluates
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Measures the ratio of H+s to OH-s
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Something that releases hydrogen ions is this...
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Acidic, with a pH of 0-6
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Something that releases OH ions is this...
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Alkaline, with a pH of 8-14
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Maximum number of bonds for any given atom
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Four bonds
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Types of bonds allowed in a molecular formula
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Single, double, and triple bonds
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What atoms share when bonded
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Electrons -- two per single bond, four per double bond, and six per triple bond
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Type of bond that is considered weak on its own
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Hydrogen bond
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A hydrogen atom can have only one of this type of bond
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Covalent bond
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Atoms with which hydrogen often forms hydrogen bonds
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Oxygen and Nitrogen
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Surface tension is produced by the interaction of this
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Numerous hydrogen bonds
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A covalent bond is...
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Equal sharing of electrons between atoms
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What constitutes an ionic bond?
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Electrons that are not equally shared between atoms, where an electron is closer to one of the atoms
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An atom that carries either a positive or negative charge
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An ion
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Definition of "organic"
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Contains carbon
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Elements that make up sugars
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Carbon, hydrogen, and oxygen
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Ratio of hydrogen to oxygen in a saccharide
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2:1 ratio
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Glucose and fructose are examples of these
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Monosaccharides
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Lactose, sucrose, and maltose are examples of these
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Disaccharides
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Joining two smaller compounds by removing water
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Dehydration synthesis
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Starches, glycogen, and cellulose are examples of these
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Polysaccharides
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Adding a water molecule to break a molecular bond
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Hydrolysis
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What carbohydrates are made of
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Carbon, oxygen, and hydrogen
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Fats, oils, waxes, and cholesterol are examples of these
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Lipids
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Difference between sugars and lipids, in terms of structure
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Both are made of carbons, oxygens, and hydrogens, but the H to O ratio for lipids is much higher than sugars
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A triglyceride is made of what?
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Three fatty acids and one glycerol molecule
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Identify:
A - What this structure represents B - The green area C - The red area |
A - A triglyceride
B - Glycerol C - Three fatty acids |
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What does this structure represent?
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An amino acid
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Name the components of an amino acid
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- The amino group NH(2)
- The carboxyl group, COOH - The R group (the amino acid's sidechain) |
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Glycine has the ________ sidechain
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Simplest sidechain
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Lysine has a _______ sidechain
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A complex sidechain
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These are the building blocks of proteins
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Amino acids
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A dipeptide is...
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Two amino acids joined together
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The bond between the carboxyl group of one amino acid and the amino group of another is called this
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The peptide bond
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What is the job of an enzyme?
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It speeds up the rate of reactions within a cell - an organic catalyst
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Vitamins act as _______
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Coenzymes (aka 'cofactors') that help enzymes do their job
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An enzyme is a type of ________
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Protein
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Enzymes have active sites where these can "dock"
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Reactants or substrates
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When reactants A and B interact with an enzyme, what is the result?
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Product C and the original enzyme
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The single structure of an enzyme with its substrates is called __________
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The enzyme-substrate complex
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What two circumstances can break/disrupt enzyme bonds?
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High temperatures and high or low pH
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What makes an enzyme sluggish?
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Low temperature
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A saturated enzyme means what?
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There are more substrates than enzymes to service them
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The semipermanent disruption of bonds in a molecule (causing enzymes and other proteins to lose their shape)
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Denaturation
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A lipid bilayer and proteins make up what?
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The fluid mosaic model of a cell membrane
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What two things are required for diffusion to occur in a cell?
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1. A membrane that is permeable to the diffusing substance
2. An area outside the cell of lower concentration (of the substance that is being transported) |
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The difference in concentration of a substance across an area is called what?
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Concentration gradient
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The molecule that acts as a source of energy inside a cell
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ATP (adenosine triphosphate)
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Name the three methods of transport for a cell
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1. Diffusion
2. Facilitated transport 3. Active transport |
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Active transport requires what?
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Energy, in the form of ATP
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The diffusion of water is called what?
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Osmosis
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Transport of a substance from INSIDE a cell to OUTSIDE, via a membrane-bound pocket
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Endocytosis
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Transport of a substance from OUTSIDE a cell to INSIDE, via a membrane-bound pocket
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Exocytosis
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A form of "cell eating" for endocytosis of large particles
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Phagocytosis
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A form of "cell drinking" for endocytosis of liquid particles
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Pinocytosis
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Something that gets dissolved in a solution
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Solute
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A liquid that permits a solute to exist within it
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Solvent
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Functions of the Gogli Apparatus
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1. Packages things, like proteins, to be sent outside the cell
2. Transports these to the cell membrane to be excreted |
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Type of endoplasmic reticulum where protein synthesis occurs
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Rough ER
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A single-celled organism
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Protozoan
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What a protozoan's contractile vacuoles do
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Expel extra water from the organism to maintain a water balance with its environment
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Long, thin fibers that give a cell shape and motility
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Microfilaments
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A cytoskeleton is made of what?
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Microfilaments and microtubules
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Microfilaments and microtubules are made of what?
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Different kinds of proteins
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A type of cell that has a membrane around the nucleaus
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Eukaryote
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Cells that do not have a membrane around their nuclei
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Prokaryotes
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A long, whip-like structure of microtubules that enables a cell to move
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Flagellum
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Short, hair-like structures of microtubules that help cells move through oar-like motions
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Cilia
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Key components missing from prokaryote cells
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- Arranged chromosomes
- Mitochondria - ER - Gogli apparatus |
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What prokaryote cells have that eukaryotes don't
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A cell wall
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Bacteria are a type of these
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Prokaryotes
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Round, pea-shaped bacteria
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Cocci
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Rod-shaped bacteria
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Bacilli
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Corkscrew-shaped bacteria
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Spirilla
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Components of a virus
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A nucleic acid surrounded by a protein coat called a capsid
Also a piece of RNA or DNA to inject into a human cell |
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What antibiotics do to bacteria
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They disable the cell wall
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A small, intracellular, membrane-enclosed sac that stores or transports substances
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Vesicle
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The biochemical process where glucose is broken down
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Glycolysis
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What a glucose molecule breaks down into...
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Pyruvic acid
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How a cell generates ATP
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Through glycolysis
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After glycosis, where does the cell send the pyruvates?
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To the mitochondria for processing
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What does the mitochondria do with pyruvic acid?
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Converts it to acetyl CoA molecules and puts it through the Krebs cycle
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What is required for the Krebs cycle?
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A oxaloacetate and acetyl CoA molecule that enter as a citrate
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Another term for the Krebs cycle
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Citric acid cycle
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What does the Krebs cycle do?
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- pulls hydrogens and electrons off the molecules and uses them to create NAD+ and FAD
- generates ATP |
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What does the mitochondria need FADH₂ and NADH for?
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To make ATP
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When a molecule loses an electron, it is called _______
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Oxidation
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When a molecule gains an electron, it is called _______
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Reduction
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NADH and FADH₂ are what?
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A reduced forms of NAD+ and FAD. They are coenzymes that take on electrons
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Where is the electron transport chain located?
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On the inner mitochondrial membrane
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An organic compound that consists of three joined structures: a nitrogenous base, a sugar, and a phosphate group
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Nucleotide
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A nucleotide used to drive active transport and fuel chemical reactions such as photosynthesis and cellular respiration
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ATP (Adenosine Triphosphate)
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The process in eukaryotes that moves protons down a concentration gradient to produce ATP
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Oxidative phosphorylation
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The breakdown of glucose and its successor molecules in the presence of oxygen
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Aerobic respiration
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Average aerobic respiration yield of ATP, per glucose molecule
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34-36 ATP molecules
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Organisms that conduct aerobic respiration
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Aerobes
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Average anaerobic respiration yield of ATP, per glucose molecule
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2 ATP molecules
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Organisms that conduct anaerobic respiration
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Anaerobes
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Products of yeast and bacteria fermentation
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Ethanol and carbon dioxide
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Products of muscle cell fermentation
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Lactic acid
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Aerobic process that transports carrier molecules (ultimately) to an oxygen molecule
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Electron transport chain
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Innermost portion of the mitochondria
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Matrix
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An organism that produces its own food
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Autotroph
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An organism that gets food from consuming something else
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Heterotroph
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A metal ion activator that is bound to an enzyme and is required for catalysis
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Inorganic cofactor
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Another name for an organic, non-protein part of an enzyme
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Cofactor or coenzyme
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An element's atomic number indicates what?
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The number of protons in the nucleus
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What an atom is called when it contains the same number of protons and electrons
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Uncharged
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The three-dimensional space that electrons travel through is called...
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Electron cloud,
electron shell, or orbital |
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The outermost occupied energy level of an element
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Valence shell
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What makes an atom more stable?
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When all its electrons are paired
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What makes an atom the most stable?
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When the valence shell is full
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Two or more atoms held together by a shared electron is called _________
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A molecule
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What is formed when two or more different atoms bind together chemically to form a unique substance
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A compound
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Molecules with regions of partial charge are called...
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Polar molecules
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The breakdown of a compound into its components
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Decomposition reaction
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When one compound breaks into a new compound and a free reactant
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Replacement reaction
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Reactions that require energy
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Endothermic reactions
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Reactions that release energy
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Exothermic reactions
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Certain chemicals dissociate in water because water molecules are _______
|
Polar
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A chemical that accepts protons when dissolved in water
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A base
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A chemical that donates protons when dissolved in water
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An acid
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What is produced when an acidic solution is neutralized in a basic solution?
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Salt and water
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Water is unique because it _______ when solidifying in response to cold
|
Expands
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Frozen water is less dense than liquid because of its _________
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Crystalline structure
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Water in an environment moderates high temperatures because of its _____________
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High specific heat
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The name "carbohydrate" stands for what?
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Carbon + water, which also illustrates the 2:1 ratio of Hydrogen to Oxygen in this molecule
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Plants store energy by synthesizing _________
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Starches
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A polysaccharide that many animals use for short-term energy storage (especially in muscle and liver tissue)
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Glycogen
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The lipids in cell membranes
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Phospholipids
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Some lipids serve as ________ or ________
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Vitamins or hormones
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Lipids used for long-term storage
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Fats
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Large unbranched chains of amino acids
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Proteins
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Two groups of nucleic acids
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Deoxyribonucleic acid (DNA)
Ribonucleic acid (RNA) |
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Suffix for enzymes
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-ase
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DNA and RNA are composed of chains of these
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Nucleotides
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The nitrogen base in DNA indicated by the letter A
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Adenine
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The nitrogen base in DNA indicated by the letter C
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Cytosine
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The nitrogen base in DNA indicated by the letter G
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Guanine
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The nitrogen base in DNA indicated by the letter T
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Thyamine
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What Watson & Crick discovered and modeled in the 1950s
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Double-helix structure of DNA
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A sugar (pentose) attached to a phosphate group and a nitrogenous base
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Nucleotide composition
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The scientist who discovered one celled bacteria ("animalcules")
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Antonie van Leeuwenhoek
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When the light microscope was invented
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Mid-1600s
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First scientist to use the term "cells"
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Robert Hooke
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Scientists who developed cell theory
|
Matthias Schleiden and Theodor Schwann
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First principle of cell theory
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All living things are made up of one or more cells
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Second principle of cell theory
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Cells are the basic unit of life
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Third principle of cell theory
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All cells come from pre-existing cells
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Projections of a cell extending from the membrane, containing digestive enzymes
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Microvilli
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Where free ribosomes are found
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Cytoplasm
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Task of the endoplasmic reticulum (ER)
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To deliver lipids and proteins to certain areas within the cytoplasm
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Folds of the internal mitochondrian membrane
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Cristae
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The speculation that mitochondria evolved from primitive bacteria that lived symbiotically with eukaryotic cells more than 2 billion years ago
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Endosymbiont hypothesis
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Points at which the double nuclear membrane fuses together, forming a passageway
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Nuclear pores
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What facilitated diffusion requires
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Specialized proteins
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When the water concentration is equal inside and outside a cell
|
Isomotic or isotonic
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All types of energy transformation processes that occur as chemicals are broken apart or synthesized within a cell
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Cellular metabolism
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Process whereby cells build molecules and store energy in the form of chemical bonds
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Anabolism
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Breaking down molecules and releasing stored energy
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Cotabolism
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The part of the chloroplast that contains chlorophyll
|
Grana
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First phase of photosynthesis
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Light reaction (photolysis or noncyclic photophosphorylation)
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Second phase of photosynthesis
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Dark reaction (CO₂ fixation)
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Sum total of genetic info
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Genome
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A series of bases on a DNA strand that together code for a polypeptide
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Gene
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The function of a protein or group of proteins
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Trait
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Code proteins that form organs and structural characteristics
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Structural genes
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Code proteins that determine functional or physiological events (e.g. growth), regulating when other genes start or stop encoding proteins
|
Regulatory genes
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The transfer of genetic material from one bacterial cell to another
|
Transduction
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A virus that targets bacteria
|
Bacteriophage
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The process of bacteria absorbing and incorporating pieces of DNA from their environment
|
Transformation
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Long chains of subunits that make up chromosomes
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Nucleosomes
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Small proteins at the core of a nucleosome
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Histones
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DNA wrapped around histone proteins
|
Chromatin
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Pairs of chromosomes of similar size and shape, but not necessarily identical
|
Homologs
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Different forms of corresponding genes
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Alleles
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DNA-cutting enzymes found in bacteria and harvested from them for use
|
Restriction Enzymes (Endonucleases)
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What restriction enzymes are usually named for
|
The host of origin
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Process by which a cell distributes its duplicated chromosomes to two daughter cells
|
Mitosis
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The three phases of the interphase cell cycle
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G₁ phase
S phase G₂ phase |
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Cell cycle marked by a high rate of metabolism and protein synthesis, including the most cell growth and organelle production
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G₁ phase
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The cycle where a cell prepares for division by replicating the DNA and proteins necessary to form a new set of chromosomes
|
S Phase
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Cell cycle where more proteins are produced for cell division and the centrioles are replicated
|
G₂ phase
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Four phases of mitosis
|
Prophase
Metaphase Anaphase Telephase |
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Asexual cell reproduction
|
Mitosis
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Process of producing four daughter cells, each with a single, unduplicated set of chromosomes
|
Meiosis
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Where meiosis occurs
|
Reproductive organs
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A cell containing half the chromosomes of the parent
|
Haploid
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Parent cell of a haploid, containing a normal set of paired chromosomes
|
Diploid
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Another name for the haploid cells produced by meiosis
|
Gametes
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Name for a cell that indicates the number of DNA copies present
|
Ploidy
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Hydrogen binding between water molecules is called ______
|
Cohesion
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Base pair rules
|
A - T
G - C |
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How are DNA base pairs linked?
|
Through hydrogen bonds
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Top three causes of DNA mutation
|
1. Chemicals
2. Radiation 3. Viruses |
|
|
Result of DNA replication
|
Two double-stranded DNA molecules, with the original strands divided between the two
|
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Name for DNA replication where the result is two double DNA strands with half old and half new material
|
Semiconservative Replication
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3 steps of protein synthesis
|
1. Transcription
2. RNA processing 3. Translation |
|
|
Products of DNA transcription
|
mRNA (messenger RNA)
tRNA (transfer RNA) rRNA (Ribosomal RNA) |
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Process that "unzips" a portion of DNA, reads a gene for encoding a particular protein, and replicates it.
|
Transcription
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Process where the non-coding sequence on a strand of mRNA is removed
|
Post-transcriptional processing
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Three bases in a DNA or RNA sequence which specify a single amino acid
|
Codon
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The process of turning RNA into a protein
|
Translation
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|
A chain of about 80 nucleotides and three anticodon that creates a link between the language of nucleotides and that of amino acids
|
tRNA (Transfer RNA)
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|
Unattached base nucleotides
|
Anti-codon
|
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|
Each strand of tRNA has one of these attached to it
|
A specific amino acid
|
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|
Where translation occurs in a cell
|
At the ribosomes
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The process of checking for errors in newly replicated DNA
|
Proofreading
|
|
|
This nucleotide is substituted for thymine in RNA
|
Uracil (U)
|
|
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How many strands does RNA have?
|
One
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The strand of DNA that directly encodes a protein
|
Sense strand
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The complementary strand to a coding strand of DNA
|
Antisense strand
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What determines the codon that a strand of tRNA reads from a strand of mRNA?
|
The amino acid accompanying the tRNA -- because it bonds to its matching codon
|
|
|
How the ends of a DNA strand are indicated
|
3' (three prime) and 5' (five prime)
|
|
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A DNA code error that does not affect the amino acid sequence coding
|
Silent mutation
|
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Deletion or insertion errors in DNA coding (which cause dramatic changes in the amino acid sequences of proteins)
|
Frameshift mutations
|
|
|
The enzyme that unwinds the DNA double helix for replication
|
Helicase
|
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What is the purpose of tRNA?
|
To bring amino acids to the ribosome during protein synthesis
|
|
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Total number of human chromosomes in human cells
|
23 pairs
|
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Attraction of unlike substances
|
Adhesion
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The ability of a substance to wick up another substance into it
|
Capillary action
|
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|
Large, organic molecules
|
Macromolecules
|
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A macromolecule composed of repeating structural units, connected by covalent chemical bonds
|
Polymer
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A single molecular unit
|
Monomer
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Similar clusters of atoms in molecules
|
Functional Groups
|
|
|
When two sugar molecules are joined by losing a water molecule
|
Glycosidic linkage
|
|
|
Union of a cofactor and an enzyme
|
Holoenzyme
|
|
|
Water and dissolved substances, such as proteins and nutrients, found in a cell's cytoplasm
|
Cytosol
|
|
|
Aerobic respiration is carried out by this organelle
|
Mitochondria
|
|
|
Products of photophosphorylation
|
ATP and energy-rich NADPH
|
|
|
Another name for the "dark reaction" of photosynthesis
|
Calvin-Benson Cycle
|
|
|
The process of taking CO₂ from the atmosphere and the energy in ATP and NADPH to create a glucose module.
|
Calvin-Benson Cycle, aka CO₃ cycle or "dark reaction"
|
|
|
Examples of organic polymers
|
Polysaccharides
Proteins DNA |
|
|
The final process of animal cell division where the cell is pinched into two cells with identical chromosomes and their own nuclei
|
Cytokinesis
|
|
|
The isolation and line-up of an individual's chromosomal pairs
|
Karyotype
|
|
|
One strand of a double-stranded chromosome
|
Chromatid
|
|
|
Each strand of the same double-stranded chromosome
|
Sister chromatid
|
|
|
Where two chromatids on a double-stranded chromosome attach
|
centromere
|
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|
Product of meiosis
|
Haploid cells
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Genetic variation is introduced by this process, when one or more sections of chromatid (from one chromosome) exchange with corresponding sections of chromatid from its homologous chromosome during meiosis
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Crossing over
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The process of making enzymes and other proteins from DNA
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Protein Synthesis
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Natural continuous read order of a DNA strand
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3' --> 5'
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Short segments of complementary DNA that polymerase reads when assembling the 5' --> 3' strand
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Okazaki segments
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Enzymes that break and re-join the double helix during replication, preventing the formation of knots
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Topoisomerases
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Each leading strand and Okazaki strand is initiated with this
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RNA Primase
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The Y-shaped junction that forms as DNA is unwound for replication
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Replication fork
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Enzyme that unwinds the DNA during replication
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Helicase
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Enzyme that reads and assembles the new strand in DNA replication
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DNA polymerase
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Because the 5' --> 3' oriented strand takes longer to duplicate during replication, it is called the ____________
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Lagging strand
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Process of adding DNA nucleotides to the complementary strands during replication
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Elongation
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When an insertion error results in the subsequent nucleotides being shifted one position over
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Frameshift mutation
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Radiation or chemicals that cause mutations
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Mutagens
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Mutagens that activate uncontrolled cell growth
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Carcinogens
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________ are the end products of metabolic processes regulated by enzymes
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Traits
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Replication cycles of viruses
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Lytic
Lysogenic |
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Viruses are organized by ______
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The type of nucleic acid they contain (DNA or RNA)
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Some viruses directly use their RNA to make what?
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mRNA
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A minuscule cell parasite that, incapable of living independently, penetrates a cell and takes control of the cell’s machinery to reproduce itself (later contaminating other cells)
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Virus
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These use an enzyme called reverse transcriptase to make a DNA compliment of their RNA, to incorporate into host DNA
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Retrovirus
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How bacteria reproduce
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Binary Fission
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Process of binary fission
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The chromosome replicates and the cell wall divides (there is no nucleus to divide)
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Another name for the singular, circular DNA molecule that bacteria contain
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Naked chromosome (lacking the normal histones and proteins of a normal chromosome)
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The three main mechanisms by which bacteria acquire new DNA
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Conjugation
Transduction Transformation |
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The process by which bacteria pick up DNA from their environment, often from the remnants of DNA from dead bacterial cells
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Transformation
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The transfer of genetic material between bacteria through cell-to-cell contact
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Conjugation
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The exchange of DNA between bacteria using bacterial viruses (bacteriophage) as an intermediate
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Transduction
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This is used as a template for translation, to create a protein
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mRNA
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Region of the DNA to which RNA polymerase binds -- a site which includes the initiation site
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Promoter
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The stretch of DNA transcribed into RNA for a specific protein
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Transcription unit, consisting of one gene in eurkaryotes
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In transcription, what enzyme adds the bases to the growing RNA molecule?
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RNA polymerase
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In what direction does the RNA molecule elongate?
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5' to 3' direction
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Where is the promoter located on DNA?
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About 100 nucleotides before the initiation site
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The promoter usually contains this sequence of DNA about 25 nucleotides "upstream" from the initiation site
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TATA box, rich in thymine and adenine bases
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Why do transcription factors need to bind to the TATA box in the DNA promoter?
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Because RNA doesn't recognize the TATA box on its own, but it can recognize this complex
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What signals RNA polymerase to stop transcribing and release the RNA molecule?
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Termination sequence in the DNA
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A DNA or RNA segment that doesn't contain information for protein synthesis
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Intron
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A DNA or RNA segment that contains information for protein synthesis
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Exon
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The process of removing introns from RNA and sticking the exons back together
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Splicing
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During processing, ______ is added to the 5' end of RNA, and ______ is added to the 3' end, to protect the resulting mRNA strand
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GTP cap
Poly-A tail |
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RNA transcription takes place in a cell's _______, while translation (protein synthesis) takes place in the cell's _______.
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Nucleus
Cytoplasm |
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How many nucleotides provide the code to create a single amino acid?
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Three (a triplet code called a codon)
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Usually, more than one codon can code for the same amino acid -- why is this good?
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It protects the cell from mutations that might otherwise make it impossible to code a given amino acid
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First scientists to work on cracking the RNA code for amino acids
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Nirenberg and Matthei
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If 61 of the possible 64 codons all code for a single amino acid, what do the last three serve as?
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Stop codons - signaling the end of translation
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What amino acid does the start codon of RNA also code for?
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Methionine (AUG)
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The sequence of mRNA codons being translated, relative to the starting point
|
Reading frame
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What is needed for translation
|
mRNA - containing the codons
tRNA - matches a specific amino acid |
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tRNA carries _______ at its 3' end
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An amino acid
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The enzyme that helps amino acids attach to tRNA
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Aminoacyl-tRNA synthetase (specific to the amino acid)
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The 5' end of tRNA has what?
|
An anti-codon that helps it attach to the complementary codon on mRNA, serving as an adapter between the amino acid and the mRNA
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Composition of ribosomes
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rRNA and several proteins
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What does the smaller subunit of a ribosome do in translation?
|
Has a binding site for the mRNA
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What does the larger subunit of a ribosome do in translation?
|
Has two binding sites for two tRNA molecules - the P-site and A-Site, where the P-site holds the tRNA with the growing polypeptide
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What are the two kinds of ribosomes?
|
Free (floating in the cytoplasm) and bound (attached to make the rough ER)
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A collection of ribosomes translating the same mRNA strand
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Polyribosome
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An amino acid sequence on a polypeptide that targets the polypeptide to its final destination
|
Signal sequence
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What is the most notable difference between viruses and bacteria?
|
Bacteria is a single-celled organism; viruses do not have cells
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The bacteriophage life cycle that results in the death of the host cell
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Lytic cycle
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The bacteriophage life cycle that results in the replication of the viral genome without harming the host
|
Lysogenic cycle
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Sometimes called "junk DNA", this highly condensed chromatin occupies about 10-25% of a eukaryotic genome
|
Heterochromatin - chromatin not used to create proteins
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What is heterochromatin important for?
|
Proper chromosome condensation and movement during cell division
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Most genes are found in this chromatin which is only condensed during cell division
|
Euchromatin
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The function of centromeres on chromatids
|
Provide handles for the long fibers to use when pulling the chromatin apart
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Ends of a chromosome
|
Telomeres
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What three factors affect whether a cell continues from G₁ to the S phase?
|
Availability of nutrients
Density of nearby cells Growth factors |
|
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What does S phase stand for?
|
DNA Synthesis
|
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What does the G in G₁ and G₂ phase stand for?
|
Gap
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What does M phase consist of?
|
Mitosis and Cytokinesis
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|
Inside the centromere of a pair of sister chromatids is a ______ that functions as an attachment site for the mitotic spindle
|
kinetocore
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|
During mitosis, what is responsible for the precise distribution of chromosomes to the daughter cells?
|
The mitotic spindle, an array of microtubules
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|
|
In this mitosis phase:
Chromatin condenses into chromosomes The nucleolus disappears Centrosomes migrate and synthesis spindle fibers Nuclear envelope disappears Spindle fibers attach to sister chromatids Nonkinetochore microtubules grow toward the center of the cell |
Prophase
|
|
|
In this mitosis phase, chromosomes line up at the midpoint of the cell and the sister chromatids separate
|
Metaphase
|
|
|
This imaginary plane cuts through the nucleus at the exact midpoint of the cell, where it will divide
|
The metaphase plate
|
|
|
In this mitosis phase, poles move apart, lengthening the cell as spindle fibers pull sister chromatids away from each other, toward opposite poles
|
Anaphase
|
|
|
In this phase of mitosis:
The nuclear envelops form Nucleoli reappear The spindle apparatus disassembles |
Telophase
|
|
|
How does plant cell cytokinesis differ from that of animal cells?
|
In plants, a double membrane called the cell plate forms and a new cell wall is formed between the two membranes of that plate
|
|
|
In which phase do cells spend most their time?
|
Interphase
|
|
|
Four types of asexual reproduction
|
Parthenogenesis
Binary fission Budding Fragmentation with regeneration |
|
|
In this form of reproduction, a new organism develops as an outgrowth of the body of the parent
|
Budding
|
|
|
In this form of reproduction, the body of the parent breaks into parts that reform whole organisms
|
Fragmentation with regeneration
|
|
|
What are the names for the primary two phases of meiosis?
|
Meiosis I and Meiosis II -- two rounds of cell division
|
|
|
The pairing of homologous chromosomes
|
Synapsis
|
|
|
X-shaped figures where two chromatids have exchanged (crossed over) and are visible by light microscope in meiosis I
|
Chiasmata
|
|
|
How does meiosis prophase I differ from the prophase stage of mitosis?
|
Synapsis occurs, as well as crossing over among sister chromatids
|
|
|
How does meoisis metaphase I differ from metaphase in mitosis?
|
Chromosomes line up on the metaphase plate in pairs and each chromosome pair connects to only one pole
|
|
|
Why is the random alignment of chromosome pairs important in meiosis metaphase I?
|
It ensures independent assortment (random distribution of maternal and paternal members of each pair to the daughter cells)
|
|
|
The rest period between meiosis telophase I and prophase II
|
Interkinesis or Interphase II
|
|
|
What is the purpose of meiosis II?
|
To separate the sister chromatids in the daughter cells (converting two diploid to four haploid cells)
|
|
|
What is the difference between meiosis II and mitosis?
|
The end result - four haploid cells vs. two diploid cells
|
|
|
Given that humans have 23 pairs of chromosomes, how many different gametes can one individual create?
|
8.4 million
|
|
|
How many cross over events typically occur in a single human chromosome?
|
Two or three
|
|
|
The formation of new combinations of genes by crossing over
|
Recombination
|
|
|
Small pieces of DNA that may be present in the cytoplasm of a prokaryote
|
Plasmids
|
|
|
What is the cell wall of eubacteria made of?
|
Peptidoglycan
|
|
|
Two categories of eubacteria determined with gram staining
|
Gram-positive (cells that retained the violet dye)
Gram-negative (cells that did not retain the dye) |
|
|
What does the capsule of a prokaryote do?
|
Helps the prokaryote stick to surfaces and each other
|
|
|
Two nutritional categories of prokaryotes
|
Autotrophs build from CO2
Heterotrophs build materials from organic compounds |
|
|
How are prokaryotes categorized by the energy they use?
|
Phototrophs - get their energy from sunlight
Chemotrophs - get their energy from chemicals in the environment |
|
What kind of molecule is this?
|
Carbohydrate (cellulose)
|
|
|
This organelle is responsible for the synthesis of lipids, metabolism of carbohydrates and calcium concentration, drug detoxification, and attachment of receptors on cell membrane proteins.
|
Smooth endoplasmic reticulum
|
|
|
What is unique about unsaturated fats, as opposed to saturated fats?
|
They have a kink or bend at the position of the double bond, so the molecules do not pack together as easily
|
|
|
A method used in biochemistry and molecular biology to separate DNA or RNA molecules by size
|
Agarose gel electrophoresis
|
|
|
This reaction allows pieces of DNA to be readily and rapidly copied, or amplified
|
PCR (polymerase chain reaction)
|
|
|
What is an independent variable?
|
The variable that is changed by the scientist
|
|
|
What is released by organisms in the process of making glucose and other organic molecules that help to power the metabolisms
|
Heat
|
|
|
These macromolecules have a three-dimensional structure
|
Proteins
|
|
|
A protein's primary structure describes this
|
The amino acid sequence of the peptide chains
|
|
|
The 3-D shape that results from hydrogen bonding between the amino and carboxyl groups of adjacent amino acids makes up this
|
A protein's secondary structure
|
