Question 1

Which of the following best describes the law of segregation as proposed by Mendel?

Accepted Answer

Alleles for a trait separate during gamete formation, so each gamete receives only one allele.

Question 2

A heterozygous tall pea plant ($$Tt) is $$crossed with a homozygous short pea plant ($$tt). $$What is the expected phenotypic ratio of tall to short plants in the offspring?

Accepted Answer

$$1:1$$

Question 3

In a test cross, a plant with genotype $$Rr ($$round seeds) is crossed with a plant with genotype $$rr ($$wrinkled seeds). What proportion of the offspring will have round seeds?

Accepted Answer

$$0.50$$

Question 4

Which of the following scenarios best illustrates incomplete dominance?

Accepted Answer

A red-flowered plant crossed with a white-flowered plant produces pink-flowered offspring.

Question 5

A true-breeding black dog ($$BB) is $$crossed with a true-breeding yellow dog ($$bb). $$Black is dominant to yellow. What is the probability that a yellow pup appears in the F2 generation?

Accepted Answer

$$0.25$$

Question 6

Which of the following best describes co-dominance?

Accepted Answer

Both alleles are fully expressed in the phenotype of the heterozygote.

Question 7

In a flower color cross, red ($$RR) $$and white ($$rr) $$produce pink ($$Rr) $$offspring. If two pink-flowered plants are crossed, what is the expected phenotypic ratio of red:pink:white in the offspring?

Accepted Answer

$$1:2:1$$

Question 8

Gaucher disease is autosomal recessive. If a woman who is heterozygous for Gaucher disease has a child with a man who does not have the disorder, what is the probability that the child has Gaucher disease?

Accepted Answer

$$0.00$$

Question 9

A man who has PKU ($$pp) $$and a woman who is a carrier ($$Pp) $$have a child. What is the probability that their child is also a carrier?

Accepted Answer

$$0.50$$

Question 10

Two heterozygous Kermode bears mate and produce a cub. What is the probability that their cub is female and has a white coat, given that white coat is caused by two recessive alleles?

Accepted Answer

$$0.13$$

Question 11

Which of the following best explains why a test cross is used in genetics?

Accepted Answer

To determine the genotype of an individual with a dominant phenotype.

Question 12

Some chicken breeds have three different feather colors: black, white, and blue. When a pure-breeding chicken with black feathers is crossed with a pure-breeding chicken with white feathers, all offspring have blue feathers. What type of inheritance is most likely responsible?

Accepted Answer

Incomplete dominance

Question 13

If two chickens with blue feathers (from an incomplete dominance cross) are mated, what is the expected phenotypic ratio for their offspring?

Accepted Answer

$$1$$ black $$: 2$$ blue $$: 1$$ white

Question 14

A female Kermode bear with a black coat gives birth to twin cubs, one with a black coat and one with a white coat. What is the most likely genotype of the female parent bear?

Accepted Answer

$$Bb$$

Question 15

Which of the following statements about Mendel's law of independent assortment is correct?

Accepted Answer

Alleles for different traits are inherited independently if they are on different chromosomes.

Question 16

Which of the following is an example of co-dominance in humans?

Accepted Answer

AB blood type, where both A and B antigens are expressed.

Question 17

A woman who is a carrier for an autosomal recessive disorder and a man who is not a carrier have a child. What is the probability that the child is a carrier?

Accepted Answer

$$0.50$$

Question 18

Which of the following best distinguishes incomplete dominance from co-dominance?

Accepted Answer

Incomplete dominance results in a blended phenotype, while co-dominance results in both alleles being fully expressed.

Question 19

If a plant with genotype $$Rr ($$round seeds) is self-pollinated, what is the expected genotypic ratio in the offspring?

Accepted Answer

$$1 RR$$ $$: 2 Rr$$ $$: 1 rr$$

Patterns and Processes of Inheritance: Mendelian Genetics, Extensions, and Probability

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