Question 1

Which of the following best describes a phenotype?

Accepted Answer

The observable characteristics resulting from the genotype.

Question 2

If a child inherits the genotype Bb for hair color, where B is dominant for black hair and b is recessive for blonde hair, what will be the child's hair color?

Accepted Answer

Black hair

Question 3

How many pairs of autosomal chromosomes are present in humans?

Accepted Answer

22 pairs

Question 4

Which of the following genotypes is homozygous recessive?

Accepted Answer

$$bb$$

Question 5

A woman who is a carrier for X-linked color blindness (genotype $$X^N X^n) $$and a man who is not color blind ($$X^N Y) $$have a son. What is the probability that their son will be color blind?

Accepted Answer

$$50\%$$

Question 6

Which statement about X-linked inheritance is correct?

Accepted Answer

Males are more likely to express X-linked recessive traits because they have only one X chromosome.

Question 7

In a Punnett square for a cross between two heterozygous parents ($$Bb 	imes Bb$$), what is the expected ratio of offspring phenotypes for a dominant trait?

Accepted Answer

$$3:1$$

Question 8

Which of the following best describes a heterozygous genotype?

Accepted Answer

Two different alleles for the same gene

Question 9

A female with genotype $$X^N X^n ($$carrier for color blindness) and a male with genotype $$X^n Y ($$color blind) have a daughter. What is the probability that their daughter will be color blind?

Accepted Answer

$$25\%$$

Question 10

Which of the following is true regarding recessive alleles?

Accepted Answer

They are only expressed in the phenotype if present on both alleles.

Question 11

If a parent has genotype $$BB$$ and another has $$bb$$, what will be the genotype of all their offspring?

Accepted Answer

$$Bb$$

Question 12

Which of the following is NOT a possible genotype for a female in X-linked inheritance?

Accepted Answer

$$X^N Y$$

Question 13

A man with genotype $$X^n Y ($$color blind) and a woman with genotype $$X^N X^N ($$not color blind) have children. What is the probability that their daughters will be carriers?

Accepted Answer

$$100\%$$

Question 14

Which of the following best explains why males cannot be carriers for X-linked recessive traits?

Accepted Answer

Males have only one X chromosome, so any recessive allele on it will be expressed.

Question 15

If both parents are heterozygous for a trait ($$Bb$$), what is the probability that their child will be homozygous recessive?

Accepted Answer

$$25\%$$

Question 16

Which of the following is a correct description of a carrier in X-linked inheritance?

Accepted Answer

A female with one dominant and one recessive allele ($$X^N X^n)$$

Question 17

Which of the following is the correct formula for calculating the probability of a child inheriting a recessive trait from two heterozygous parents?

Accepted Answer

$$P = \frac{1}{4}$$

Question 18

Which of the following statements about alleles is correct?

Accepted Answer

Alleles are different forms of the same gene located at the same locus on homologous chromosomes.

Question 19

A woman who is not color blind ($$X^N X^N) $$and a man who is color blind ($$X^n Y) $$have a son. What is the probability that their son will be color blind?

Accepted Answer

$$0\%$$

Question 20

Which of the following best describes the genotype $$X^n X^n$$?

Accepted Answer

Homozygous recessive female (color blind)

Unit 6 -

Study Guide - Practice Questions

Study Guide - Flashcards