Chapter 11 Biology

When Gregor Mendel crossed a tall plant with a short plant, the F1 plants inherited

• four alleles from each parent.

• one allele from each parent.

• three alleles from each parent.

• two alleles from each parent.

The different forms of a gene are called

• traits.

• hybrids.

• pollinations.

• alleles.

If a pea plant has a recessive allele for green peas, it will produce

• both green peas and yellow peas if it also has a dominant allele for yellow peas.

• green peas if it does not also have a dominant allele for yellow peas.

• yellow peas if it does not also have a dominant allele for green peas.

• green peas if it also has a dominant allele for yellow peas.

If a pea plant's alleles for height are tt, what is true of its parents?

• Both parents were tall.

• Both parents contributed a recessive allele.

• Both parents contributed a dominant allele.

• Both parents were short.

In the P generation, a tall plant was crossed with a short plant. Short plants reappeared in the F2 generation because

• the alleles for tallness begin to disappear in the F2 generation

• the alleles for both heights segregated when the F1 plants made gametes.

• the allele for shortness becomes dominant in the F2 generation.

• the allele for shortness becomes more common in the F2 generation.

When you flip a coin, what is the probability that it will come up tails?

• 1

• 1/4

• 1/2

• 1/8

The principles of probability can be used to

• predict the traits of the offspring of genetic crosses.

• decide which organisms are best to use in genetic crosses.

• determine the actual outcomes of genetic crosses.

• determine which species should be used in genetic crosses.

A heterozygous tall pea plant is crossed with a short plant. The probability that an F1 plant will be tall is

• 100%

• 50%

• 25%

• 75%

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

• dominant.

• homozygous.

• hybrid.

• heterozygous.

In the Punnett square shown in Figure 11-1, which of the following is true about the offspring resulting from the cross?

• About half are expected to be short.

• About three fourths are expected to be tall.

• All are expected to be short.

• All are expected to be tall.