Chapter 11.2 Assessment

2.B. An F1 plant that is homozygous for shortness is crossed with a heterozygous F1 plant. What is the probability that a seed from the cross will produce a tall plant? Use a Punnett square to explain your answer and to compare the probable genetic variations in the F2 plants.

50 percent; the Punnett square should show a cross between a homozygous short plant (tt) and a heterozygous tall plant (Tt).

2.A. What is independent assortment?

During gamete formation, pairs of alleles for a gene segregate, or separate, independently of each other.

3.B. Why is the fruit fly an ideal organism for genetic research?

Fruit flies are small, easy to keep in the laboratory, and produce large numbers of offspring in a short period of time.

1.B. How are Punnett squares used to predict the outcomes of genetic crosses?

Punnett squares are used to show all of the combinations of alleles that might result from a cross and the likelihood that each might occur.

1.A. What is probability?

The likelihood that a particular event will occur.

3.A. How did Gregor Mendel contribute to our understanding of inherited traits?

The patterns of inheritance he observed form the basis of modern genetics.