AP BIOLOGY
Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
Pyruvate dehydrogenase is an enzyme that converts pyruvate to acetyl. Acetylis further metabolized in the
in a reaction containing pyruvate and pyruvate
Krebs cycle. A researcher measured the accumulation of acetyldehydrogenase under several different conditions (Figure 1).
Figure 1. Accumulation of acetyl-
1.
under different conditions
Which of the following best describes the cellular location where pyruvate dehydrogenase is most likely active?
(A) The cytosol
(B)
The lysosomes
(C)
The nucleus
(D) The mitochondrial matrix
AP Biology
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Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
Directions: This group of questions consists of five lettered headings followed by a list of phrases or sentences. For each
phrase or sentence, select the one heading to which it is most closely related. Each heading may be used once, more than
once, or not at all.
This group of questions refers to molecules of the following substances.
(A) Cytochrome
(B) FADH2
(C) NAD+
(D) NADP+
(E) Oxygen (O2)
2.
An intermediate electron acceptor for oxidations that occur in both glycolysis and in Krebs cycle reactions
(A) Cytochrome
(B)
FADH2
(C)
NAD+
(D) NADP+
(E)
3.
Oxygen (O2)
Coenzyme that transfers electrons from the Krebs cycle to the mitochondrial electron-transport chain at a lower
energy level than that of electrons entering at the beginning of the chain
(A) Cytochrome
(B)
FADH2
(C)
NAD+
(D) NADP+
(E)
4.
Oxygen (O2)
A researcher claims that increased atmospheric carbon dioxide levels cause increased growth rates in plants.
Which of the following statements best supports the researcher’s claim?
5.
(A)
Atmospheric carbon dioxide is produced by the burning of fossil fuels, which are formed from the remains of
living organisms such as plants.
(B)
Atmospheric carbon dioxide is a byproduct of cellular respiration, which is a metabolic process that occurs in
plants and other living organisms.
(C)
Atmospheric carbon dioxide typically enters plant leaves through stomata, which plants rely on for regulating
gas exchange with the atmosphere.
(D)
Atmospheric carbon dioxide is the raw material for photosynthesis, which plants rely on for producing sugars
and other organic compounds.
ATP serves as a common energy source for organisms because
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AP Biology
Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
(A) it is the smallest energy molecule
(B)
it stores the least energy of any energy source
(C)
its energy can be easily transferred to do cellular work
(D) it is extremely stable and can be stored in the cell for long periods of time
(E)
traces of it have been found in fossils of ancient organisms dating back to the beginning of life on Earth
To investigate bacterial metabolism, a researcher divided a population (culture) of Staphylococcus capitis bacteria into
of
two sets of culture tubes containing glucose. The researcher added a chemical to one set of tubes and measured the
the cultures at -minute intervals as the bacteria metabolized the glucose into lactic acid. The data are shown in Table 1.
TABLE 1. AVERAGE CHANGE IN
Time (min)
6.
IN CONTROL AND TREATMENT GROUPS OVER A
PERIOD
Average
(
of Control
)
Average
(
-MINUTE
of Treatment
)
Which of the following best describes the process by which the bacteria are breaking down the glucose to produce
lactic acid?
(A) The bacteria are breaking down sugars in the absence of oxygen.
(B)
The bacteria are creating a
(C)
The bacteria are using their mitochondria to break down glucose in the presence of oxygen.
(D) The bacteria are producing
7.
gradient to synthesize more
.
in the Krebs cycle that is then converted into lactic acid.
Which of the following was the dependent variable in the researcher’s experiment?
(A) Time
(B)
(C)
Glucose concentration
(D) Lactic acid concentration
AP Biology
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Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
8.
Erwin Chargaff investigated the nucleotide composition of
. He analyzed
from various organisms and
measured the relative amounts of adenine ( ), guanine ( ), cytosine ( ), and thymine ( ) present in the
of
each organism. Table 1 contains a selected data set of his results.
Table 1. Nucleotide composition of sample
Organism
from selected organisms
Relative Amounts of Bases
Octopus
33.2
17.6
17.6
31.6
35.2
64.8
Chicken
28.0
22.0
21.6
28.4
43.7
56.4
Rat
28.6
21.4
20.5
28.4
42.9
56.0
Grasshopper
29.3
20.5
20.7
29.3
41.2
58.6
Wheat
27.3
22.7
22.8
27.1
45.5
54.4
Which of the following statements best explains the data set?
9.
(A)
Since the
and the
add up to approximately 50 percent in each sample, adenine and guanine
molecules must pair up in a double-stranded
molecule.
(B)
Since the
and the
are approximately the same in each sample, adenine and thymine molecules must
molecule.
pair up in a double-stranded
(C)
Since the
tail at one end.
(D)
and the
add up to approximately 50 percent in each sample, cytosine and thymine
Since the
molecules must both contain a single ring.
is greater than the
in each sample,
molecules must have a poly-
A gene that influences coat color in domestic cats is located on the chromosome. A female cat that is
heterozygous for the gene (
) has a calico-colored coat. In a genetics experiment, researchers mate a calico) with an orange-colored male cat (
) to produce an
generation. The researchers
colored female cat (
generation and plan to use the data to perform a chi-square goodness-of-fit
record observations for the cats in the
test for a model of -linked inheritance. The data for the chi-square goodness-of-fit test are presented in Table 1.
Table 1. Data for the chi-square goodness-of-fit test
Phenotype
Genotype
Observed
Expected
Calico-colored female
15
10
Orange-colored female
6
10
Black-colored male
11
10
Orange-colored male
8
10
The researchers calculate a chi-square value of 4.6 and choose a significance level of
following statements best completes the chi-square goodness-of-fit test?
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AP Biology
. Which of the
Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
(A) The null hypothesis can be rejected because the chi-square value is greater than the critical value.
(B)
The null hypothesis can be rejected because the chi-square value is less than the critical value.
(C)
The null hypothesis cannot be rejected because the chi-square value is greater than the critical value.
(D) The null hypothesis cannot be rejected because the chi-square value is less than the critical value.
10.
The energy required to run the Calvin cycle reactions of photosynthesis comes from which two substances produced
during the light-dependent reactions?
(A) ATP and NADPH
(B)
ADP and PO4
(C)
H+ and PO2
(D) O2 and CO2
(E) H2O and CO2
11.
The carbon 'that makes up organic molecules in plants is derived directly from
(A) combustion of fuels
(B)
carbon fixed in photosynthesis
(C)
carbon dioxide produced in respiration
(D) carbon in the lithosphere
(E)
12.
coal mines
Cells that contain only circular chromosomes are most probably which of the following?
(A) Protist cells
(B)
Fungal cells
(C)
Bacterial cells
(D) Plant cells
(E)
13.
Animal cells
Which of the following best describes a characteristic of
that makes it useful as hereditary material?
(A) There are many different types of nucleotide bases that can be incorporated into
.
(B)
The nucleotide bases can also be used to provide the energy needed for reproduction.
(C)
Nucleotide bases can be randomly replaced with different nucleotide bases to increase variation.
(D) Nucleotide bases in one strand can only be paired with specific bases in the other strand.
14.
Which of the following statements about mitochondrial chemiosmosis is NOT true?
(A) A proton gradient is established across the inner membrane of the mitochondrion.
(B)
The potential energy released from the mitochondrial proton gradient is used to produce ATP.
(C)
The mitochondrial proton gradient provides energy for muscle contraction.
(D) Proteins embedded in the inner mitochondrial membrane play an important role in ATP synthesis.
(E)
Heat energy is required to establish the electron transport chain.
AP Biology
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Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
15.
According to the chemiosmotic theory (chemiosmotic coupling), the energy required to move protons from the
mitochondrial matrix to the intermembrane space against a concentration gradient comes most directly from
(A) photons of red or blue light
16.
(B)
the hydrolysis of ATP
(C)
the breakdown of high-energy fatty acids in
the mitochondrial matrix
(D)
electrons flowing along the electron transport
chain
(E)
substrate-level phosphorylation
A researcher observes that when two heterozygous plants with red flowers are crossed, the resulting offspring
include plants with red, white, or pink flowers. The researcher proposes the null hypothesis that flower color is the
result of independent assortment and incomplete dominance. The researcher calculates a chi-square value of
.
Assuming two degrees of freedom, which of the following is the correct interpretation of the chi-square analysis,
using a -value of
?
(A) The null hypothesis should be rejected because the critical value is less than the calculated value.
(B)
The null hypothesis should not be rejected because the critical value is less than the calculated value.
(C)
The null hypothesis should not be rejected because the critical value is greater than the calculated value.
(D) The null hypothesis should be rejected because the critical value is greater than the calculated value.
17.
The diploid number of chromosomes in the cell of a domesticated dog is . Which of the following options
checkpoint, meiosis, and
includes the correct number of chromosomes in a cell after each cellular process (
fertilization, respectively)?
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AP Biology
Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
(A)
(B)
(C)
(D)
After
After
After
Checkpoint
Meiosis
Fertilization
After
After
After
Checkpoint
Meiosis
Fertilization
After
After
After
Checkpoint
Meiosis
Fertilization
After
After
After
Checkpoint
Meiosis
Fertilization
AP Biology
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Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
The following questions refer to the following DNA strand and table of codons.
18.
The mRNA transcribed from the DNA would read
(A) 5’ TAG TTC AAA CCG CGT AAC AAT 3’
(B)
5’ ATC AAG TTT GGC GCA TTG TAA 3’
(C)
5’ AUC AAG UUU GGC GCA UUG UAA 3’
(D) 5’ AAU CAA UGC GCC AAA CUU GAU 3’
(E)
19.
5’ AUU GUU ACG CGG UUU GAA CUA 3’
Humans have a diploid number ( ) of . Which of the following statements best predicts the consequence if
meiosis did not occur during gametogenesis?
(A) The gametes would get larger from one generation to the next.
(B)
The chromosome number would double with each generation.
(C)
The chromosome number would be halved with each generation.
(D) The chromosome number would triple with each generation.
20.
Which of the following best explains how continuity of genetic information in cells is ensured across generations?
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AP Biology
Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
(A) Replication uses a parental strand of
(B)
(C)
.
molecules are shaped like a double helix with a constant diameter throughout.
Transcription copies the information in
(D) Cells contain different polymerases for
21.
as a template to create a new strand of
into an
transcript.
replication and transcription.
In most vertebrates, the sperm cell normally contributes which of the following to the new organism?
(A) Many mitochondria
(B)
Significant amounts of RNA
(C)
A haploid complement of chromosomes
(D) Most of the cytoplasm of the zygote
(E)
22.
Two sex chromosomes
Cortisol is a hormone produced in response to stress, including starvation, in humans. Which of the following is
most likely an immediate effect of a starvation-induced increase in cortisol secretion?
(A) Increased activation of the immune system
(B)
Increased urine production by the kidneys
(C)
Increased bone and collagen formation
(D) Increased mobilization of fatty acids from fat cells
23.
Within the cell, many chemical reactions that, by themselves, require energy input (have a positive free-energy
change) can occur because the reactions
(A) may be coupled to the hydrolysis of ATP
(B)
take place very slowly
(C)
take place when the cells are at unusually high temperatures
(D) are catalyzed by enzymes
(E)
are aided by various metal ions that act as catalysts
AP Biology
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Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
24.
Figure 1. Model of crossing over between homologous chromosomes, indicating crossing over rate of selected loci.
During prophase replicated homologous chromosomes pair up and undergo synapsis. What testable question is
generated regarding synapsis and genetic variability by Figure 1 ?
(A) Is the distance between two gene loci related to crossover rate?
(B)
Does crossing over occur more often in some chromosomes than in others?
(C)
Is crossing over inhibited by methylation?
(D) Is crossing over promoted by methylation?
25.
The diagram above illustrates which of the following processes?
(A) Crossing-over
(B)
Base pair substitution
(C)
Duplication
(D) Deletion
(E)
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Posttranscriptional processing
AP Biology
Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
26.
The events listed below generally take place during meiosis.
I. Synapsis occurs.
II. Crossing-over is completed.
III. Condensation of chromosomes begins.
IV. Separation of homologous chromosomes begins.
Which of the following is the correct sequence of these events?
(A) I, II, III, IV
(B)
II, I, III, IV
(C)
III, I, II, IV
(D) III, IV, II, I
(E)
27.
IV, II, III, I
In sheep, eye color is controlled by a single gene with two alleles. When a homozygous brown-eyed sheep is
crossed with a homozygous green-eyed sheep, blue-eyed offspring are produced. If the blue-eyed sheep are mated
with each other, what percent of their offspring will most likely have brown eyes?
(A) 0%
(B)
25%
(C)
50%
(D) 75%
(E)
100%
28.
In the pedigree above, circles represent females, squares represent males, and shaded figures represent individuals
expressing a specific trait. The expression of this trait is most likely due to which of the following?
(A) Sex-linked dominant inheritance
(B)
Sex-linked recessive inheritance
(C)
Autosomal dominant inheritance
(D) Autosomal recessive inheritance
(E)
A codominant relationship of a single pair of alleles
AP Biology
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Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
29.
Which of the following normally leads to the production of functional messenger RNA in eukaryotic cells?
(A) A decrease in the rate of ribosome synthesis
(B)
The removal of portions of RNA known as intervening sequences (introns)
(C)
A decrease in RNA polymerase activity
(D) The replication of new messenger RNA molecules from existing messenger RNA molecules
(E)
30.
The formation of peptide bonds between adjacent nucleotides
If 2n = 48 for a particular cell, then the chromosome number in each cell after meiosis would be
(A) 96
(B)
48
(C)
24
(D) 12
(E)
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6
AP Biology
Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
31.
Directions: Answers must be in essay form. Outline form is not acceptable. Labeled diagrams may be used to
supplement discussion, but in no case will a diagram alone suffice. It is important that you read each question
completely before you begin.
The flow of genetic information from DNA to protein in eukaryotic cells is called the central dogma of biology.
(a) Explain the role of each of the following in protein synthesis in eukaryotic cells.
•
•
•
•
•
RNA polymerase
Spliceosomes (snRNPs)
Codons
Ribosomes
tRNA
Please respond on separate paper, following directions from your teacher.
(b) Cells regulate both protein synthesis and protein activity. Discuss TWO specific mechanisms of protein
regulation in eukaryotic cells.
Please respond on separate paper, following directions from your teacher.
(c) The central dogma does not apply to some viruses. Select a specific virus or type of virus and explain how it
deviates from the central dogma.
Please respond on separate paper, following directions from your teacher.
Directions: Answers must be in essay form. Outline form is not acceptable. Labeled diagrams may be used to supplement
discussion, but in no case will a diagram alone suffice. It is important that you read each question completely before you
begin.
In many ways, all organisms in a food web can be said to be solar-powered. The producer level of the food web is
responsible for the transformation of the solar energy into a form that can be used by other living organisms.
AP Biology
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Test Booklet
AP BIOLOGY EXAMS 2021/2022 ACADEMIC YEAR
32.
Discuss the role of green plants in transforming the Sun’s energy into a form that can ultimately be used by
heterotrophs.
Please respond on separate paper, following directions from your teacher.
33.
Directions: Answers must be in essay form. Outline form is not acceptable. Labeled diagrams may be used to
supplement discussion, but in no case will a diagram alone suffice. It is important that you read each question
completely before you begin.
The cell cycle is fundamental to the reproduction of eukaryotic cells.
(a) Describe the phases of the cell cycle.
Please respond on separate paper, following directions from your teacher.
(b) Explain the role of THREE of the following in mitosis or cytokinesis.
•
•
•
•
Kinetochores
Microtubules
Motor proteins
Actin filaments
Please respond on separate paper, following directions from your teacher.
(c) Describe how the cell cycle is regulated and discuss ONE consequence of abnormal regulation.
Please respond on separate paper, following directions from your teacher.
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AP Biology