Genetics Final (Quiz Questions)

Front 1

The separation of the two genetic “factors” of the same locus is described by the Mendelian process of

Back 1

segregation

Front 2

When reciprocal crosses produce identical results the trait is

Back 2

autosome-linked

Front 3

A mating that is expected to produce 50% homozygous and 50% heterozygotes is:

Back 3

A_bb x aabb

Front 4

A cross between two AaBbCcDd plants yields ______ different genotypes in
the offspring. Assume independent assortment.
a) BB x Bb
b) Bb x Bb
c) Bb x bb
d) two of above
e) all of the above

Back 4

all of the above

Front 5

A cross between two AaBbCcDd plants yields ______ different phenotypes in the
offspring. Assume independent assortment

Back 5

81

Front 6

How many different types of gametes are produced by an individual with genotype
AABbccDDeeFFgg?

Back 6

16

Front 7

You perform a cross of two plants that are heterozygous for four genes.
What proportion of the offspring do you expect to be homozygous for all four
dominant alleles?

Back 7

2

Front 8

You perform a cross of two plants that are heterozygous for four genes. What proportion of the offspring do you expect to be homozygous for all four dominant alleles?

Back 8

1/256

Front 9

In a hypothetical animal, tails can be jagged or straight. Assume that these phenotypes are under the control of a single gene with two alleles, J (jagged) dominant to j (straight). A cross of two jagged-tail animals produced 267 jagged and 88 straight progeny. What are the genotypes of the parents?

Back 9

Jj and Jj

Front 10

Which of the following dihybrid crosses will produce offspring in a 1:1 ratio?

Back 10

AaBB x aaBB

Front 11

Consider five independently assorting gene pairs, A/a, B/b, C/c, D/d and E/e, where
each demonstrates complete dominance (A_, B_, C_, D_, and E_) and recessiveness (aa, bb, cc, dd and ee). An individual with genotype AaBbCCddEe is crossed to an individual with genotype AABbCcDdEe. What is the probability of obtaining an offspring with genotype AABbCcDdee?

Back 11

1/64

Front 12

Consider the two parents in question 11, AaBbCCddEe and AABbCcDdEe. What is the probability of obtaining an offspring that is dominant for all five traits?

Back 12

9/32

Front 13

The normal cloven-footed condition in swine is produced by the recessive allele m, while the mule-footed condition is produced by the dominant allele M. White coat color is governed by the dominant allele of another locus B, and black by its recessive allele b. A black mule-footed sow (female pig) is mated with a white cloven-footed boar (male pig). All of their 36 offspring are white, but 17 have mule feet and 19 have cloven feet. What are the probable genotypes of the parents?

Back 13

Mmbb and mmBB, respectively

Front 14

Suppose you perform a cross between two true-breeding stocks of garden peas, with respect to two characteristics of their flowers. The first parent had red, axial flowers and the second had white, terminal flowers; all F1 individuals were like the first parent. If you obtained 1000 F2 offspring by allowing the F1s to self-hybridize, about how many of them would expect to have red, terminal flowers? (Assume that the genes assort independently)

Back 14

190

Front 15

In a typical monohybrid cross of true-breeding tall (TT) and short (tt) Pisum sativum parents, what would be the expected number of heterozygous tall plants in the F2 offspring, assuming that T is dominant to t, and 80 offspring are counted?

Back 15

40

Front 16

Which of the following statements is TRUE?
a) an individual with the genotype AaBBccDdEeFfGg produces 8 different gametes
b) a cross between two AaBbCc parents yields 27 different genotypes
c) a cross between two AaBb parents yields a 9:3:3:1 phenotypic ratio
d) two of the above
e) all of the above

Back 16

two of the above

Front 17

A woman has hemophilia (an X-linked recessive disorder). This means that:
a) her mother must also have had hemophilia.
b) all of her sons will have hemophilia.
c) half of her daughters will have hemophilia.
d) half of her daughters will be carriers of hemophilia.
e) two of the above

Back 17

b) all of her sons will have hemophilia

Front 18

Consider five independently assorting gene pairs, A/a, B/b, C/c, D/d and E/e, where each demonstrates complete dominance (A-, B-, C-, D-, and E-) and recessiveness (aa, bb, cc, dd and ee). An individual with genotype AaBbCCddEe is crossed to an individual with genotype AABBCcDdEe. What is the probability of obtaining an offspring that is dominant for all five traits?

Back 18

3/8

Front 19

Albinism is an autosomal recessive disorder. Two parents with normal pigmentation have an albino child. What is the probability that their next 4 children will consist of two albinos and two with normal pigmentation, in any order?

Back 19

Hint: use binomial equation!

27/218

Front 20

Albinism is an autosomal recessive condition characterized by absence of melanin pigment from the skin, eye and hair. Two carriers of albinism marry and plan to have four children. Assume a 1:1 sex ratio. What is the probability that all their children will be normal girls?

Back 20

0.020

Front 21

In the garden pea, tall vine (D) is dominant over dwarf (d), green pod (Y) is dominant over yellow (y) and round seed (W) is dominant over wrinkled (w).
A tall, yellow, round plant is crossed to a dwarf, green, round one. The following ratios occurred in the F1 generation: 3/8 tall, green, round; 3/8 dwarf, green round; 1/8 tall, green, wrinkled; and 1/8 dwarf, green, wrinkled. What is the genotype of the two parental plants?

Back 21

DdyyWw and ddYYWw

Front 22

Albinism is an autosomal recessive condition characterized by absence of melanin pigment from the skin, eye and hair. Two carriers of albinism marry and plan to have four children. What is the probability that 3 children will be normal and one will be albino?

Back 22

0.421

Front 23

What are the dimensions of the Punnett square for the self-cross of AaBbCc?

Back 23

none of these choices

Front 24

What phenotypic ratio is expected in the progeny of the cross AaBb x aabb, if complete dominance is assumed?

Back 24

1:1:1:1

Front 25

In the leghorn breed of chicken, white plumage is dominant over colored plumage, feathered shanks are dominant over clean shanks, and pea comb is dominant over single comb. The three genes assort independently. A homozygous white, feathered, pea-combed chicken is crossed with a colored, clean, single-combed chicken, and the F1 progeny are allowed to interbreed. What proportion of the F2 class will produce only white, feathered pea-combed chicken if mated to colored, clean, single-combed birds?

Back 25

1/64

Front 26

Which of the following statements is TRUE?
a) An individual with the genotype AaBbccDDEeFFGG produces 8 different gametes.
b) A cross between two AaBbCcDd parents yields 81 different genotypes.
c) Both A and B
d) Neither A nor B

Back 26

Both A and B

Front 27

Which of the following genotypes is expected to be the most common among the offspring of the cross AaBb x AaBb?
a) AABB
b) aabb
c) AAbb
d) AaBb
e) AaBB

Back 27

AaBb

Front 28

Hemophilia and colorblindness are both X-linked, recessive traits. A hemophiliac woman marries a colorblind man. Assume that both are otherwise normal. If meiosis occurs normally for both parents, what phenotypes are possible among their offspring?

Back 28

phenotypically normal daughters and hemophiliac sons

Front 29

Consider the garden pea cross WwGg X WwGg, where W = round, w = wrinkled, G = yellow and g = green. What proportion of the offspring is expected to be round, green AND true-breeding?

Back 29

1/16

Front 30

Colorblindness is an X-linked recessive trait. A phenotypically normal man and a colorblind woman have four sons. What is the probability that all four of them are color blind? Assume no new mutations.

Back 30

1

Front 31

Colorblindess is an X-linked recessive trait. A couple has a color-blind son and a daughter with normal vision. Which of the following conditions is MOST likely?
a) the father was heterozygous for colorblindess
b) the father was homozygous for colorblindess
c) the father was colorblind
d) the mother was colorblind
e) the mother was heterozygous for colorblindess

Back 31

e) mother was heterozygous

Front 32

Barbara’s first son has hemophilia, an X-linked recessive disorder. What is the probability that her next son will be hemophiliac?

Back 32

cannot be determined without knowing Barbara's genotype

Front 33

Colorblindness is an X-linked recessive trait. A couple has two sons: one with normal vision and the other is color-blind. Which of the following statements HAS to be TRUE?
a) the father is colorblind
b) the mother is colorblind
c) the father has normal color vision
d) the sons are not true siblings
e) none of the above

Back 33

none of the above

Front 34

Consider the cross AaBbCCDd x aaBBccDd. If the genes are independently assorting, how many different genotypes are possible in the offspring?
a) 8
b) 16
c) 24
d) 32
e) none of these choices

Back 34

none of these choices

Front 35

Duchenne muscular dystrophy is an X-linked recessive disease. A phenotypically normal couple wants to start a family. The woman’s brother has the disease. What is the probability that the couple’s first child will be affected?

Back 35

1/8

Front 36

Colorblindness is an X-linked recessive trait. A couple has two sons: one with normal vision and the other is color-blind. Which of the following statements HAS to be TRUE?
a) the father is colorblind
b) the mother is colorblind
c) the father has normal color vision
d) the sons are not true siblings
e) none of the above

Back 36

none of the above

Front 37

A woman with normal vision has a son. The woman’s maternal grandfather is color-blind. What is the probability that the son is colorblind, if his father is normal? Assume there are no other color-blind individuals in the pedigree.

Back 37

1/4

Front 38

The addition rule is termed the:

Back 38

"or" rule

Front 39

The multiplication rule is used when the probabilities are:

Back 39

independent

Front 40

What is the probability of throwing two dice and obtaining two 3s?

Back 40

1/36

Front 41

What is the probability of throwing 2 dice and obtaining identical numbers?

Back 41

1/6

Front 42

What is the probability of flipping a coin six times in a row and getting three heads in a row, followed by three tails?

Back 42

1/64

Front 43

What is the probability of flipping a coin six times in a row and getting three heads and three tails?

Back 43

5/16

Front 44

What is the probability of throwing two dice and obtaining a 4 and a 6?

Back 44

1/18

Front 45

A family has five kids. What is the probability that they are all female?

Back 45

1/32

Front 46

A family has five kids. What is the probability that they are three males and two females?

Back 46

5/16

Front 47

A family has five kids. What is the probability that they consist of at least one female?

Back 47

none of these choices

Front 48

A family has five kids. What is the probability that the first and last born are male?

Back 48

1/4

Front 49

Consider a standard deck of 52 cards. You pick two cards in a row, without returning the first card to the deck. What is the probability of drawing the king of diamonds and an ace, in that order?

Back 49

0.00151

Front 50

Albinism is an autosomal recessive condition characterized by absence of melanin pigment from the skin, eye and hair. Two heterozygote carriers of albinism marry and plan a family of five. What is the probability that all their children will be normal?

Back 50

0.237

Front 51

Two heterozygote carriers of albinism marry and plan a family of five. What is the probability that 4 children will be normal and one will be albino?

Back 51

0.396

Front 52

Two heterozygote carriers of albinism marry and plan a family of five. Probability that at least 3 children will be normal?

Back 52

0.896

Front 53

Achondroplasia, a form of dwarfism, is inherited as an autosomal dominant trait. Two heterozygote achondroplastics marry and plan a family. Assume a 1:1 sex ratio and that all genotypes are compatible with survival. What is the probability that the couple's first two children will be achondroplastic males?

Back 53

9/64

Front 54

Two heterozygote achondroplastics (autosomal dominant) marry and plan a family. Probability that their first five children will consist of at least 3 achondroplastics?

Back 54

0.895