Gallery Walk

Fundamentals of Genetics

Question 1

Hitchhiker's thumb (H) is dominant to no hitchhiker's thumb (h). A woman who does not have hitchhiker's thumb marries a man who is heterozygous for hitchhiker's thumb. What is the probable genotypic ratio of their children?

A. 0% Hh: 100% hhB. 50% Hh: 50% hhC. 75% Hh: 25% hhD. 100% Hh: 0% hh

Question 2

Gregor Mendel developed an understanding of heredity through his experiments with pea plants. Two pairs of homologous chromosomes had a genotype of AaBb. All of the following are possible allele combinations that could be formed if this cell undergoes meiosis except-

A. ABB. AbC. aBD. AA

Question 3

A person can have either straight or bent pinky fingers. A woman who is homozygous for bent pinky fingers has children with a man who has straight pinky fingers. All of their children have bent pinky fingers. The trait for bent pinky fingers is an example of a trait that is

A. dominantB. recessiveC. co-dominantD. incompletely dominant

Question 4

The characteristic for curly hair (C) is dominant to the characteristic for straight hair (c). A cross between two individuals for hair type is shown in the Punnett square to the right.

What must the genotype of the parents be to produce the results shown in the Punnett square?A. homozygous dominant x homozygous dominantB. homozygous dominant x heterozygousC. homozygous recessive x homozygous dominantD. heterozygous x heterozygous

Question 5

A geneticist studying fruit flies hypothesizes that short wings are a recessive trait coded for by a single gene. Which observation is most likely to have led her to form this hypothesis?

A. Flies have wing lengths ranging from very long to very short.

B. Flies with long wings are less likely to survive.C. Flies with long wings can produce offspring with

short wings.D. Flies with short wings prefer to mate with flies with

long wings.

Question 6

Female cattle that have white coats are crossed with male cattle that have red coats. Both male and female offspring have roan coats, which are coats with both red hairs and white hairs.

Which of the following best describes the genetics of coat color in the cattle?

A. The red and white alleles are sex-linked.B. The red and white alleles are co-dominant.C. The red allele is recessive to the white

allele.D. The red allele is dominant to the white

allele.

Question 7

In tomato plants, the tall vine allele (T) is dominant to the short vine allele (t). Two tomato plants are crossed. Among the offspring plants grown from seed, 45% have tall vines and 55% have short vines.

What are the most likely genotypes of the parent plants?

A. TT and ttB. Tt and TTC. Tt and ttD. tt and tt

Question 8

In canaries, the gene for singing (S) is dominant over the gene for non-singing (s). When hybrid singing canaries are mated with non-singing canaries, what percentage of the offspring is likely to possess the singing trait?

A. 0%B. 25%C. 50%D. 100%

Question 9

Only red tulips result from a cross between homozygous red and homozygous white tulips. This illustrates the principle of—

A. dominance.B. segregation.C. independent assortment.D. incomplete dominance.

Question 10

In minks, the gene for brown fur (B) is dominant over the gene for silver fur (b). Which set of genotypes represents a cross of two brown minks that could produce offspring with silver fur?

A. Bb × BbB. BB × BbC. BB × bbD. Bb × bb

Question 11

If B represents the dominant allele for a trait, and b represents the recessive allele, in which pair of crosses must all of the offspring produced have the same phenotype?

A. Bb × bb and BB × BbB. BB × BB and Bb × BbC. Bb × bb and Bb × BbD. BB × Bb and BB × bb

Question 12

Which of the following statements best explains why offspring produced by sexual reproduction often look similar to, but not exactly the same as, their parents?

A. The offspring have genetic material from both the mother and the father.

B. The cells of the offspring contain all the dominant genes from the parents.

C. The cells of the offspring undergo mitosis many times as the offspring grow and develop.

D. The offspring have a period of embryonic development, rather than being

Question 13

In which situation could a mutation be passed on to the offspring of an organism?

A. A cell in the uterine wall of a human female undergoes a chromosomal alteration. B. Ultraviolet radiation causes skin cells to

undergo uncontrolled mitotic division.C. The DNA of a human lung cell undergoes

random breakage.

D. A primary sex cell in a human forms a gamete that

contains 24 chromosomes.

Question 14

Which best explains how meiosis is a contributing factor to genetic variation within a species?A. Meiosis reduces the number of mutations

within an organism.B. Meiosis produces daughter cells that will

contain identical chromosomes.C. Meiosis results in offspring that contain alleles

from only one parent gamete.D. Meiosis allows for crossing over of

chromosomes, resulting in new gene combinations.

Question 15

A litter of guinea pigs can vary in color. Some are solid white and some are brown and white, while others are black and white. The color and the pattern of each guinea pig are distinct from those of its parents and siblings. What process is responsible for the differences seen in each guinea pig?

A. MeiosisB. MitosisC. ReplicationD. Translation

Question 16

Which type of cell must contain a mutation in order for the mutation to be passed from a woman to her offspring?

A. blood cellB. brain cellC. egg cellD. skin cell

Question 17

The diagram to the right provides information about a carrot cell. A carrot cell contains 18 chromosomes. Which of the following diagrams illustrates the correct number of chromosomes in new cells produced by meiosis?

Question 18 Two organisms with striped fur mate and produce four offspring. Three of the offspring have striped fur but one has no stripes. The non-striped coat is probably what type of trait?A. CodominantB. Sex-linkedC. DominantD. Recessive

Question 19

The chromosomes below are found in a cell of Purple Vetch, a Texas wild flower. What is the maximum number of different combinations of the alleles that could be found in gametes produced by the flower?

A. 8B. 6C. 4D. 2

Question 20 The breed of chicken found to the right is identified by their short legs and five toes.

Based on the information in the table above, which of the following crosses will produce 25% of its offspring with four toes? A. TT x TTB. TT x TtC. Tt x TtD. tt x tt

Question 21 A cross between two mice with long tails and brown fur produced the four types of offspring listed below.

Long-tailed with brown fur Long-tailed with white fur Short-tailed with brown fur Short-tailed with white fur

Which genetic mechanism best explains the results of this cross?

A. Crossing-overB. Dependent assortmentC. Gene linkageD. Independent assortment

Question 22

Meiosis is an essential part of sexual reproduction. This is because meiosis creates sex cells that have -

A. One-fourth the normal number of chromosomes

B. One-third the normal number of chromosomesC. Three-fourths the normal number of

chromosomesD. One-half the normal number of chromosomes

Question 23

Black fur in mice (B) is dominant to brown fur (b). Short tails (T) is dominant to long tails (t). What proportion of the progeny of the cross BbTt x BBtt will have black fur and long tails?

A. 0%B. 25%C. 50%D. 75%E. 100%

Question 24

A couple has three children, all of whom have brown eyes and blond hair. Both parents are homozygous for brown eyes (BB), and one is blond (rr) while the other is a redhead (Rr). What is the probability that the next child will be a brown-eyed redhead?

A. 25%B. 50%C. 75%D. 100%

Question 25

In pea plants, the long-stem trait (L) is dominant over the short-stem trait (l). Two pea plants were crossed and produced seeds that yielded 165 long-stem plants and 54 short-stem plants. The genotypes of the parent plants were most likely —

A. LL and ll.B. Ll and LL.C. ll and ll.D. Ll and Ll.