Question

name
date
enzyme quiz - a
match the word with the correct description.

1. another word for an enzyme (biological
2. the molecule an enzyme reacts (its) with
3. measured on a scale of 0 - 14 (0 - 6 is acidic, 8 - 14 is basic)
4. formed after the enzyme reacts with a substrate
5. a protein molecule that speeds up chemical reactions
6. when this condition is too high, it causes the enzyme to change shape
7. to break down molecules
8. to combine (build) molecules
9. the \best\ conditions for an enzyme.
10. describes how fast an enzyme is working
11. all cells of an organism are engaged in many

different chemical reactions. this fact is best
supported by the presence in each cell of
thousands of different

1. chloroplasts
2. organelles
3. enzymes
4. nuclei
5. the venus flytrap is a plant that has a unique

cytosystem by which it traps and digests small
insects. which of the following is most likely the
triggering mechanism involved in the leaf
triggering the leaf to close around the prey

this substance responsible for breaking down
the venus flytraps prey more likely contains

1. glucose molecules
2. hormone molecules
3. fat molecules
4. enzyme molecules
5. base your answer to the following question on

the diagram below, which represents stages in
the digestion of a starch, and on your
knowledge of biology.

the structure labeled x most likely represents

1. an antibody
2. a receptor molecule
3. a hormone
4. an enzyme
5. base your answer to the following question on

the graph below and on your knowledge of
biology.

what is the optimum ph for the action of
intestinal proteases?

1. 12
2. 5
3. 10
4. 8

Explanation:

1. Catalysts are substances that speed up chemical reactions, and enzymes are biological catalysts. So, another word for an enzyme (biological) is “catalyst” (b).
2. The molecule an enzyme reacts (fits) with is called a “substrate” (f). Enzymes have an active - site that is complementary to the substrate.
3. pH (h) is measured on a scale of 0 - 14 (0 - 6 is acidic, 8 - 14 is basic).
4. After the enzyme reacts with a substrate, “products” (j) are formed.
5. A protein molecule that speeds up chemical reactions is an “enzyme” (a). Enzymes are proteinaceous in nature (except for some ribozymes).
6. When “temperature” (c) is too high, it causes the enzyme to change shape (denature). High temperatures break the weak bonds (like hydrogen bonds) that maintain the enzyme's tertiary structure.
7. To break down molecules is “digestion” (e). Enzymes like proteases break down proteins during digestion.
8. To combine (build) molecules is “synthesis” (i). For example, DNA polymerase synthesizes DNA molecules.
9. The “optimum” (g) are the “best” conditions for an enzyme. At the optimum temperature and pH, an enzyme has the highest activity.
10. “Reaction rate” (d) describes how fast an enzyme is working. It can be measured by the amount of product formed per unit time.

Answer:

1. b. catalyst
2. f. substrate
3. h. pH
4. j. products
5. a. enzyme
6. c. temperature
7. e. digestion
8. i. synthesis
9. g. optimum
10. d. reaction rate