Unit 3 Exam AP Biology Questions with
Verified Answers
Gelatin is a protein that is derived from collagen which is found in the bones, skin,
and connective tissue of animals. To investigate the ability of various enzymes to
digest gelatin, a group of students set up an assay involving camera film. Camera
film contains gelatin and appears black when exposed to light but turns clear as the
gelatin gets broken down. The students incubated pieces of exposed camera film in
test tubes, each containing one of three different enzyme solutions (trypsin, lipase, or
amylase) as indicated in Figure 1. The students recorded the time it took for the
enzymes to digest the gelatin in each test tube, turning the film from black to clear.
Which of the following would be the most appropriate control for this experiment? -
ANSWER-A test tube containing a piece of exposed camera film submerged in water
A researcher claims that different enzymes exhibit maximal function over different pH
ranges. To test the claim, the researcher carries out an experiment that includes
three different enzymes: pepsin, salivary amylase, and arginase. The results of the
experiment are represented in Figure 1.
Which of the following actions will provide the most appropriate negative control for
the experiment? - ANSWER-Repeating the experiment with denatured enzymes
A researcher claims that increasing the environmental temperature by 10°C will
double the rate of an enzyme-catalyzed reaction. To test the claim, the researcher
designs an experiment that uses a particular enzyme isolated from plants. The
design of the experiment is presented in Table 1. For each test tube in the
experiment, the researcher will measure the rate of product formation.
Which of the following statements best helps justify the inclusion of test tube 5 as a
control in the experiment? - ANSWER-It will provide a measurement of product
formation in the presence of a denatured enzyme.
Alcohol dehydrogenase (ADH) is an enzyme that aids in the decomposition of ethyl
alcohol (C2H5OH) into nontoxic substances. Methyl alcohol acts as a competitive
inhibitor of ethyl alcohol by competing for the same active site on ADH. When
attached to ADH, methyl alcohol is converted to formaldehyde, which is toxic in the
body.
Which of the following statements best predicts the effect of increasing the
concentration of substrate (ethyl alcohol), while keeping the concentration of the
inhibitor (methyl alcohol) constant? - ANSWER-Competitive inhibition will decrease
because the proportion of the active sites occupied by substrate will increase.
The enzyme peroxidase is found in many organisms. It catalyzes the breakdown of
hydrogen peroxide into water and oxygen gas. The rate of peroxidase activity at
different pH values was assessed by students in the lab. The students' results are
shown in graph 1.
Verified Answers
Gelatin is a protein that is derived from collagen which is found in the bones, skin,
and connective tissue of animals. To investigate the ability of various enzymes to
digest gelatin, a group of students set up an assay involving camera film. Camera
film contains gelatin and appears black when exposed to light but turns clear as the
gelatin gets broken down. The students incubated pieces of exposed camera film in
test tubes, each containing one of three different enzyme solutions (trypsin, lipase, or
amylase) as indicated in Figure 1. The students recorded the time it took for the
enzymes to digest the gelatin in each test tube, turning the film from black to clear.
Which of the following would be the most appropriate control for this experiment? -
ANSWER-A test tube containing a piece of exposed camera film submerged in water
A researcher claims that different enzymes exhibit maximal function over different pH
ranges. To test the claim, the researcher carries out an experiment that includes
three different enzymes: pepsin, salivary amylase, and arginase. The results of the
experiment are represented in Figure 1.
Which of the following actions will provide the most appropriate negative control for
the experiment? - ANSWER-Repeating the experiment with denatured enzymes
A researcher claims that increasing the environmental temperature by 10°C will
double the rate of an enzyme-catalyzed reaction. To test the claim, the researcher
designs an experiment that uses a particular enzyme isolated from plants. The
design of the experiment is presented in Table 1. For each test tube in the
experiment, the researcher will measure the rate of product formation.
Which of the following statements best helps justify the inclusion of test tube 5 as a
control in the experiment? - ANSWER-It will provide a measurement of product
formation in the presence of a denatured enzyme.
Alcohol dehydrogenase (ADH) is an enzyme that aids in the decomposition of ethyl
alcohol (C2H5OH) into nontoxic substances. Methyl alcohol acts as a competitive
inhibitor of ethyl alcohol by competing for the same active site on ADH. When
attached to ADH, methyl alcohol is converted to formaldehyde, which is toxic in the
body.
Which of the following statements best predicts the effect of increasing the
concentration of substrate (ethyl alcohol), while keeping the concentration of the
inhibitor (methyl alcohol) constant? - ANSWER-Competitive inhibition will decrease
because the proportion of the active sites occupied by substrate will increase.
The enzyme peroxidase is found in many organisms. It catalyzes the breakdown of
hydrogen peroxide into water and oxygen gas. The rate of peroxidase activity at
different pH values was assessed by students in the lab. The students' results are
shown in graph 1.
