1. Information about patterns of human heredity is more
difficult to obtain than information about patterns of
heredity in fruit flies because
A) humans have shorter life cycles and more offspring
than fruit flies
B) most humans have offspring with hidden dominant
traits
C) humans have longer life cycles and fewer offspring
than fruit flies
D) most mating in humans is carefully controlled by
genetic engineering
2. Many years ago, a scientist grew pea plants that
produced wrinkled peas. The peas from these plants
produced new plants that also produced wrinkled peas.
The scientist concluded that something in the parent
plants was being transmitted to the next generation. This
discovery is now known as
A) genetic engineering B) biological evolution
C) heredity
D) natural selection
3. Which genetic concepts best explain the fact that hybrid
parents can produce offspring with recessive
phenotypes?
A)
B)
C)
D)
codominance and polyploidy
intermediate inheritance and segregation
segregation and recombination
polyploidy and recombination
4. The crossing of two heterozygous tall pea plants usually
produces offspring in a 1:2:1 genotypic ratio for height.
This result best illustrates the genetic concept of
A)
B)
C)
D)
A) 0
B) 2
C) 3
D) 4
7. In chickens, rose comb (R) is dominant over single comb
(r). When a heterozygous rose-combed rooster is mated
with several single-combed hens, what is the expected
phenotypic ratio of the offspring?
A)
B)
C)
D)
100% rose-combed
100% single-combed
75% rose-combed and 25% single-combed
50% rose-combed and 50% single-combed
8. In summer squash, white-colored fruit is dominant over
yellow-colored fruit. If homozygous yellow-fruited
plants are crossed with heterozygous white-fruited
plants, what is the expected percentage of fruit color
produced in the offspring?
A)
B)
C)
D)
100 % yellow
100% white
50% yellow, 50% white
25% yellow, 75% white
9. Base your answer to the following question on In rabbits,
the gene for black coat color (B) is dominant over the
gene for white coat color (b). In the cross illustrated
below, rabbit member III may have genotype BB or Bb.
dominance
segregation
independent assortment
codominance
5. In a certain type of plant, tall is dominant over short, and
green seed coat is dominant over yellow seed coat. When
two plants heterozygous for both of these traits are
crossed, the offspring produced are tall, with green seed
coats; tall, with yellow seed coats; short, with green seed
coats; and short, with yellow seed coats. What do the
results of this cross illustrate?
A)
B)
C)
D)
6. In humans, the gene for polydactyly (having extra
fingers or toes) is dominant over the gene for the normal
number of digits. If parents who are both homozygous
dominant for polydactyly have four children, how many
of these children would most likely have extra fingers or
toes?
vegetative propagation
mutagenic agents
intermediate inheritance
independent assortment
Which cross should be done to help determine if rabbit
number III is heterozygous?
A)
B)
C)
D)
Cross I with II a second time.
Cross III with a rabbit having genotype BB.
Cross III with a rabbit having genotype bb.
Cross III with II.
10. Which is a true statement about people with the
genotype I AI B for blood type?
A)
B)
C)
D)
They have two alleles that are codominant.
They exhibit a type O phenotype.
They are homozygous for blood type A.
They can have only type O children.
11. If two roan cattle are crossed, what percent of the
offspring are expected to show the parental phenotype
for coat color?
A) 25%
B) 50%
C) 75%
D) 100%
12. The diagram below represents the banding pattern for
human chromosome 11, with some of the bands
labeled.
14. As male children get older, some begin to closely
resemble their fathers and have no resemblance to their
mothers. Which statement best explains this
observation?
A) Several sperm fertilized the egg, so the fertilized
egg contained more genes from their father.
B) More genes are inherited from the sperm cell of
their father than from the egg cell of their mother,
so most traits will be like those of their father.
C) More genes from their father are expressed in
traits that can be seen, and more genes from their
mother are expressed in traits that cannot be seen,
such as blood type or enzyme function.
D) Genes from their father are stronger than genes
from their mother, so the genes from their mother
are not expressed.
15. Genes for two different traits that are located next to
each other on the same chromosome would most likely
be
A) inherited separately B) codominant
C) recombined
D) inherited together
16. Base your answer to the following question on Which
process is illustrated by the diagram below?
The bands represent
A) proteins
C) starches
B) genes
D) enzymes
13. Hereditary information for most traits is generally
located in
A)
B)
C)
D)
genes found on chromosomes
chromosomes found on genes
the mitochondria of gametes
the lysosomes in the cytoplasm
A)
B)
C)
D)
crossing-over
nondisjunction
sex determination
independent assortment
17. A mutation occurs in a cell. Which sequence best
represents the correct order of the events involved for
this mutation to affect the traits expressed by this cell?
A) a change in the sequence of DNA bases joining
amino acids in sequence appearance of
characteristic
B) joining amino acids in sequence a change in
the sequence of DNA bases appearance of
characteristic
C) appearance of characteristic joining amino
acids in sequence a change in the sequence of
DNA bases
D) a change in the sequence of DNA bases appearance of characteristic joining amino
acids in sequence
18. Which statement best describes a chromosomal
alteration?
A) It never affects the phenotype of an organism.
B) It may affect the phenotype of an organism.
C) It always produces a recessive genotype in an
organism.
D) It never has an effect on the genotype of an
organism.
19. Chromosomal mutations occurring in gametes of
humans can affect the appearance of offspring because
A) many traits are usually affected
B) only one trait is usually affected
C) these mutations usually speed up embryonic
development
D) these mutations usually result in sex-linked traits
20. A mutation may be passed on to future generations if it
occurs within specialized cells of the
A) stomach
C) pancreas
B) liver
D) ovary
21. Mutations that occur in skin or lung cells have little
effect on the evolution of a species because mutations
in these cells
A)
B)
C)
D)
usually lead to the death of the organism
cannot be passed on to offspring
are usually beneficial to the organism
lead to more serious mutations in offspring
22. Which cross could produce a child with type O blood?
A) I Ai × I BI B
C) I AI B × ii
B) I AI A × I Bi
D) I Ai × I Bi
23. In humans, multiple alleles are involved in the
inheritance of what?
A) sickle-cell anemia B) sex chromosomes
C) certain blood types D) Down's syndrome
24. In a human population, the inheritance of the ABO
blood group is explained by assuming that, within the
population, the number of different kinds of alleles
responsible for blood type is
A) 6
B) 2
C) 3
D) 4
25. A human male will normally transmit the genes on his X-chromosome to
A)
B)
C)
D)
his sons, only
his daughters, only
all of his sons and daughters
half of his sons and half of his daughters
26. In humans, normal color vision (N) is dominant over
color blindness (n). A man and woman with normal
color vision produced two colorblind sons and two
daughters with normal color vision. The parental
genotypes must be
A) XN Y and XN XN
C) XN Y and XN Xn
B) XnY and XN XN
D) XnY and XnXn
27. Base your answer to the following question on the
diagram below which represents a portion of a
double-stranded DNA molecule and on your knowledge
of biology.
29. The diagram below represents genetic material.
The expression of the section labeled X may be
modified by
A)
B)
C)
D)
temperature, only
asexual reproduction
the environment
pH, only
30. The diagram below represents a portion DNA molecule.
The model of DNA represented in the diagram was
developed by
A)
B)
C)
D)
Hardy and Weinberg
Miller and Fox
Watson and Crick
Weismann and Lamarck
28. The DNA of a fly and the DNA of a gorilla are made up
of subunits that are
A) arranged in the same order in both species
B) arranged in chains of the same length in both
species
C) different bases in each of the two species
D) in different sequences in each of the two species
The letters represent different types of
A) sugar molecules
C) enzymes
B) molecular bases
D) proteins
31. What determines the kind of genes an organism
possesses?
A) type of amino acids in the cells of the organism
B) sequence of the subunits A, T, C, and G in the
DNA of the organism
C) size of simple sugar molecules in the organs of the
organism
D) shape of the protein molecules in the organelles of
the organism
35. Base your answer to the following question on the
diagram below, which represents some components
involved in cellular protein synthesis, and on your
knowledge of Biology.
32. If 15% of a DNA sample is made up of thymine, T,
what percentage of the sample is made up of cytosine,
C?
A) 15%
B) 35%
C) 70%
D) 85%
33. Which pair of molecules, when bonded together, would
most likely be found in a nucleotide of DNA?
A)
B)
C)
D)
ribose and adenine
ribose and thymine
deoxyribose and guanine
deoxyribose and uracil
34. Base your answer to the following question on the
diagram below of a DNA molecule and on your
knowledge of biology.
The type of molecule represented at A is synthesized
according to a template found in
A) DNA
C) dipeptides
B) RNA
D) amino acids
36. During replication, the strands of a double stranded
DNA molecule separate from each other when bonds
are broken between what parts of their structure?
A) nitrogenous bases
C) phosphate groups
B) 5-carbon sugars
D) amino acids
37. In the portions of the DNA molecules below, X
represents the base sequence of strand I in the original
DNA molecule, and Y represents the base sequence of
strand I in the newly formed DNA molecule.
Which activity occurs in the process of replication?
A)
B)
C)
D)
Structure 1 is hydrolyzed.
A chemical bond is broken in region 2.
Structure 3 is synthesized.
Proteins are formed in region 2.
X: A–T–G–C–C–A–T–A–G
Y: A–T–G–C–C–A–A–T–G
The base sequence in Y is an example of
A)
B)
C)
D)
polyploidy
a chromosome deletion
a gene mutation
translocation
38. Base your answer to the following question on Base your answer to the following question on the portion
of the mRNA codon chart and information below.
How would the amino acid sequence produced by the mutant strand (series II) compare to the amino acid
sequence produced by series I?
A)
B)
C)
D)
The amino acid sequence would be shorter.
One amino acid in the sequence would change.
The amino acid sequence would remain unchanged.
More than one amino acid in the sequence would change.
39. Which situation would most likely produce a gene
mutation in a squirrel?
A) The squirrel stops using its claws for digging.
B) The squirrel is exposed to radiation for several
days.
C) Oak trees gradually become less common.
D) The weather becomes wetter for a short period of
time.
40. Coded instructions that are passed from one generation
to the next can be most directly changed by the
processes of
A)
B)
C)
D)
passive transport, natural selection, and synthesis
selective breeding, replication, and absorption
recombination, mutation, and genetic engineering
evolution, reproduction, and digestion
41. Which condition would most likely produce a change in
the gene pool of a population?
A)
B)
C)
D)
a large population
random mating in the population
migrations out of the population
no mutations in the population
42. Base your answer to the following question on the
diseases and their causes listed below
A. Flu–influenza virus
B. Lung cancer–smoking
C. Cystic fibrosis–genes
D. Dysentery–parasitic amoeba
Which disease would individuals have the greatest
difficulty preventing in themselves?
A) A
B) B
C) C
D) D
43. What will most likely occur as a result of changes in
the frequency of a gene in a particular population?
A)
B)
C)
D)
ecological succession
biological evolution
global warming
resource depletion
44. The gene frequency for a particular trait in a population
was determined to be 80% A (dominant allele) and 20%
a (recessive allele). Fifty years later, the gene frequency
was determined to be 60% A and 40% a. What does
this change indicate about the gene pool?
A)
B)
C)
D)
It has remained stable.
It is evolving.
It has become predominantly recessive.
It lacks mutations.
45. The study of natural events that affect gene frequencies
in sexually reproducing groups of organisms is known
as
A)
B)
C)
D)
comparative biochemistry
population genetics
recombinant DNA technology
genetic counseling
46. Base your answer to the following question on the
information below and on your knowledge of biology.
A large population of green aphids lives in a field and
feeds on wild rose plants.
According to the Hardy-Weinberg principle, the
stability of the aphid gene pool is maintained partly by
the
A)
B)
C)
D)
type of food the aphids eat
type of habitat in which the aphids live
color of the aphids
large size of the aphid population
47. According to the Hardy-Weinberg principle, the gene
pool of a population will remain stable if
A)
B)
C)
D)
no mutations occur
the population is small
individuals migrate into and out of the population
nonrandom mating occurs by artificial selection
48. According to the Hardy-Weinberg principle, which
factor occurring in a population would cause a change
in the gene pool?
A)
B)
C)
D)
maintenance of a large population
an increased mutation rate
random mating
no migration