exam 2 module 6 Enzymes Flashcards
enzymes
catalyzes (speeds up) a chemical reaction without being consumed. Most enzymes are proteins, although there are some that are RNA.
enzymes
a) catalyst
b) activation energy(amount of energy needed to start a reaction)
c) substrates and products(bring reactants (also called substrates) into contact with one another so that less energy is required for a reaction to proceed to form a product.
d) active site(region to which a substrate binds)
e) Enzymes are reusable.
f) Enzymes can denature.
i) Sensitivity to environmental conditions (pH, temperature, salt level)
cofactors
substances that must be present for an enzyme to catalyze a chemical reaction
examples: Some cofactors are metals such as zinc, iron, and copper. For example, magnesium ions (Mg2+) help stabilize many important enzymes.
cofactors
a) coenzymes- Cofactors that are organic molecules are called coenzymes.(Diets lacking in vitamins can lead to reduced enzyme function)hint vitamins
b) metabolic pathways- linked series of chemical reactions occurring within a cell. Cells precisely control the rates of their chemical reactions. If they did not, they might produce too much or too little of vital compounds, which could have deleterious effects on the cell.
i) negative feedback- One way to regulate a metabolic pathway is by negative feedback (also called feedback inhibition). Negative feedback is a regulatory mechanism in which a change in a condition triggers action that reverses the change.
enzyme inhibitors
enzyme’s substrate fits like a puzzle piece into the enzyme’s active( picture)
enzyme inhibitors
a) competitive inhibitors- binds to the active site of an enzyme, preventing the enzyme from binding with its substrate.
b) noncompetitive inhibitors- to a spot on an enzyme other than the active site of the enzyme. This alters the enzyme’s shape, so it can no longer bind to its substrate.
