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19 Cards in this Set
- Front
- Back
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What is the initial input needed to start the reaction called?
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Activation Energy
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Why can't you just add heat in order to jump start the reaction?
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- Heat can denature and coagulate proteins and enzyms
-not all reactions need activation energy. |
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What is an enzyme?
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A catalyst used to speed up reactions. (Usually a protein)
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How does a catalyst speed up reactions?
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It lowers the activation energy required for a reaction by bringing together the molecules that are reacting.
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Describe what a catalyst does.
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-It is effective in small amounts
-Doesn't take place in the reaction itself (matchmaker) -Can be reused. |
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What is a substrate? What are some examples?
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The molecule on which the enzyme acts.
- Lactose/Lactase -Sucrose/Sucrase -Lipids/Lipase -Maltose/Maltase -ATP/ATPase -Protein/Protease,Peptidase |
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What is the active site?
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Where the enzyme and substrate join. The polypeptide chains fold perfectly to make a groove in the enzyme that only the specifically matching substrate can fit.
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What are the two enzyme models with active sites?
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Lock and Key Model (Puzzle piece)
Induced Fit Model (currently accepted) -A cofactor or coenzyme forces the substrate to change its shape, therefore making it latch onto the enzyme tighter. |
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What are the three factors affecting enzyme activity?
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Temperature, pH and substrate concentration.
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What does temperature do to enzymes?
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increases enzyme activity and reaction rate until 37-40*. After 40* the proteins are denatured and change their shape. (HIGH FEVER)
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What does pH do to enzymes?
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-enzymes function best within certain pH ranges
-diff [ ] of H- and OH change h- bonds in protein structure 2*. This changes the 3* shape and function. |
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What are some examples of enzymes in their proper pH range?
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Pepsin(Enzyme)-->Stomach(Site)--> ~2(pH)
Trypsin(Enzyme)-->Intestines(Site)--> ~8-9(pH) |
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What does substrate concentration do to enzymes?
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Increase the [ ] of reactants which increases rxn rate until saturation point. (Limited amount of enzymes available)
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What is the diff between coFACTORS and coENZYMES?
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F- inorganic, E- organic,
F- Fe, Zn, K, Mg hold 1+ reactants at active site E- synthesized from vitamins who are electron acceptors. |
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What are competitive inhibitors?
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Molecules that resemble substrate and compete for active site. When C.I's win, enzyme can't function properly. (THIS IS SOMETIMES GOOD ie- trypsin in pancreas, Carbon monoxide, Cyanide)
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What is Allosteric Activity?
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change in enzyme when binding REGULATORY SITE (not active)
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What is the regulatory site?
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Where Coenzymes/ cofactors latch.
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What is feedback inhibition? Example?
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When the product blocks the enzyme from making more product (like a thermostat) Testosterone.
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What is Precursor Activity? Example?
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Reactants attatch to enzymes closer to products (at regulatory site). Improves fit of enzyme with substrate at active site. This speeds up formation of product.
Penicillin (competes and prevents) |
