Question

1. which of the following best describes a heterozygous genotype?

a. having two different alleles for a gene
b. having only dominant alleles
c. having two identical alleles for a gene
d. having only recessive alleles

1. if two heterozygous individuals for a particular trait (aa x aa) have offspring, what is the genotypic ratio of the offspring?

a. 1:2:1
b. 2:1:1
c. 1:1
d. 3:1

1. which of the following represents a heterozygous genotype?

a. bb
b. ff
c. aa
d. qq

Explanation:

Question 4

A heterozygous genotype is defined as having two different alleles for a gene. Option b (only dominant alleles) and d (only recessive alleles) are homozygous if the alleles are identical, and option c (two identical alleles) is homozygous. So option a is correct.

Step1: Recall Punnett Square for Aa x Aa

When crossing two heterozygous individuals (Aa x Aa), the possible gametes from each are A and a. The Punnett square will have four cells: AA, Aa, Aa, aa.

Step2: Calculate Genotypic Ratios

Count the number of each genotype: AA (1), Aa (2), aa (1). So the genotypic ratio is 1:2:1.

A heterozygous genotype has two different alleles. Option a (BB), b (ff), and d (QQ) have identical alleles (homozygous), while option c (Aa) has A and a (different alleles), so it's heterozygous.

Answer:

a. Having two different alleles for a gene

Question 5