Chapter 10

Alleles are ______ . a. different molecular forms of a gene b. different phenotypes c. self-fertilizing, true-breeding homozygotes

A heterozygote has a ___________ for a trait being studied. a. pair of identical alleles b. pair of nonidentical alleles c. haploid condition, in genetic terms

The observable traits of an organism are its _____________ . a. phenotype b. sociobiology c. genotype d. pedigree

Second-generation offspring of a cross between parents who are homozygous for different alleles are the __________ . a. \(\mathrm{F}_{1}\) generation b. \(\mathrm{F}_{2}\) generation c. hybrid generation d. none of the above

\(\mathrm{F}_{1}\) offspring of the cross \(A A \times\) aa are __________ . a. all \(A A\) b. all aa c. all \(A a\) d. \(1 / 2 A A\) and \(1 / 2\) aa

Assuming complete dominance, crosses between two dihybrid \(\mathrm{F}_{1}\) pea plants, which are offspring from a cross \(A A B B \times a a b b,\) result in \(\mathrm{F}_{2}\) phenotype ratios of ___________ . a. 1: 2: 1 b. 3: 1 c. 1: 1: 1: 1 d. 9: 3: 3: 1

The probability of a crossover occurring between two genes on the same chromosome ___________ . a. is unrelated to the distance between them b. decreases with the distance between them c. increases with the distance between them

Two genes that are close together on the same chromosome are _________ . a. linked b. identical alleles c. homologous d. autosomes e. all of the above

Match each example with the most suitable description. dihybrid experiment monohybrid experiment homozygous condition heterozygous condition a. bb b. \(A A B B \times a a b b\) c. \(A a\) d. \(A a \times A a\)