Exam 1 Questions

Question 1

A gene that hides the effects of genotypes of different gene is

Answer 1

epistatic

Question 2

An albino mouse could have the genes to be black or gray, you can’t tell because albino is

Answer 2

epistatic

Question 3

This when one phenotype causes a variety of different traits

Answer 3

pleiotropy

Question 4

The most important feature of a tester strain is that they are

Answer 4

recessive

Question 5

To have a _____ trait, at least one parent must have the trait

Answer 5

dominant

Question 6

Replicated chromosomes line up in the middle of the cell

Answer 6

metaphase

Question 7

F1s are always

Answer 7

heterozygous

Question 8

Appearance of measurable trait

Answer 8

phenotype

Question 9

Sister chromatids separate in

Answer 9

anaphase Meiosis II

Question 10

Homologous chromosomes separate in

Answer 10

anaphase Meiosis I

Question 11

Parental strains are always

Answer 11

homozygous

Question 12

A fertilized egg is

Answer 12

zygote

Question 13

An egg or sperm cell is

Answer 13

gamete

Question 14

Homologous chromosomes synapse in

Answer 14

prophase Meiosis I

Question 15

One version of a gene is an

Answer 15

allele

Question 16

Mendel’s experiments were unusually well designed for his time because
a. made sure that his starting strains were true-breeding
b. followed crosses for several generation
c. used mathematical analysis
d. all of the above

Answer 16

d. all of the above

Question 17

In the F2 progeny of a dihybrid cross what fraction should be completely heterozygous?
a. 1/16
b. 3/16
c. 9/16
d. 1/2
e. 1/4

Answer 17

e. 1/4

Question 18

A Bull from a hornless (polled) true-breeding strain, is bred to a horned cow from a true-breeding strain. The F1s are all hornless. Horns are
a. dominant
b. recessive
c. co-dominant
d. sex-linked

Answer 18

b. recessive

Question 19

Independent assortment is revealed by which of these ratios?
a. 3:1
b. 9:3:3:1
c. 1:2:1
d. 2:1

Answer 19

b. 9:3:3:1

Question 20

When true-breeding spotted lentils are crossed with true-breeding dotted lentils, the F1s all have both spots and dots. This is an example of
a. incomplete dominance
b. pleiotrpy
c. co-dominance
d. epistasis

Answer 20

c. co-dominance

Question 21

Siamese kittens are born white, without pigment, looking like albinos. As they grow, the placed that their skin cools, such as ears, nose, tail, and feet darken because the Siamese color is caused by a _____ version of a pigment producing enzyme/gene.
a. complementary
b. conditional
c. epistatic
d. pleiotropic
e. co-dominant

Answer 21

b. conditional

Question 22

If genes assort independently with one dominant and one recessive allele of each gene, a test-crossed dihybrid characteristically produces progeny phenotype in the ratio
a. 1:1
b. 1:2:1
c. 3:1
d. 9:3:3:1
e. 1:1:1:1

Answer 22

e. 1:1:1:1

Question 23

Variable expressivity is when,
a. the genotype is usually, but not always visible in the phenotype
b. the genotype produce a range of phenotypes
c. the genotype is not always inheritable
d. the genotype causes a ordered percentage of 4 phenotypes

Answer 23

b. the genotype produce a range of phenotypes

Question 24

If there are 2 alleles in a gene then which of these is always true?
a. p + q = 1.0
b. p^2 + 2pq + q^2 = 1.0
c. q^2 = the homozygous recessive
d. all of the above

Answer 24

a. p + q = 1.0

Question 25

Humans have 23 different chromosomes. In anaphase of mitosis how many chromosomes are in a normal cell?
a. 23
b. 46
c. 69
d. 92

Answer 25

d. 92

Question 26

Which of these is not true of a sex-linked recessive trait, such as hemophilia A?
a. it cannot be passed by a father to his sons
b. it is possible for it to be carries unseen for generations in a female line
c. women cannot be affected by the condition
d. an affected mans normal daughters can have affected sons

Answer 26

c. women cannot be affected by the condition