Chapter 12 Test

Different forms of a gene are called

• hybrids.
• dominant factors.
• alleles.
• recessive factors.

Organisms that have two identical alleles for a particular trait are said to be

• hybrid.
• heterozygous.
• homozygous.
• dominant.

A Punnett square is used to determine the

• probable outcome of a cross.
• the actual outcome of a cross.
• result of incomplete dominance.
• result of meiosis.

The physical characteristics of an organism are called its

• genetics.
• heredity.
• phenotype.
• genotype.

What is the probability of flipping a coin twice and getting two heads?

• 1
• 1/2
• 1/4
• 3/4

In pea plants, the allele for yellow seeds is dominant over the allele for green seeds. Predict the genotypic ratio of offspring produced by crossing two parents that are heterozygous for this trait. Use a Punnett square to help you.

• 4 YY
• 3 yellow: 1 green
• 1 YY: 2 Yy: 1 yy
• 2 yellow : 2 green

A situation in which a gene has more than two alleles (like blood type) is known as

• complete dominance.
• codominance.
• polygenic dominance.
• multiple alleles.

A pink-flowered plant (Rr) is crossed with a white-flowered plant (rr). What is the chance that a seed from this cross will produce a purebred red-flowered plant (RR)?

• 0
• 1/4
• 1/2
• 1

Unlike mitosis, meiosis in male mammals results in the formation of

• one haploid gamete.
• three diploid gametes.
• four diploid gametes.
• four haploid gametes.

A gene map shows

• the number of possible alleles for a gene.
• the relative locations of genes on a chromosome.
• where chromosomes are in a cell.
• how crossing-over occurs.