Comprehension Questions

Section 22.1

Question 22.1

What experiments suggested that genes are not lost or permanently altered in development?

Section 22.2

Question 22.2

Briefly explain how the Dorsal protein is redistributed in the formation of the Drosophila embryo and how this redistribution helps to establish the dorsal–ventral axis of the early embryo.

Question 22.3

Briefly describe how the bicoid and nanos genes help to determine the anterior–posterior axis of the fruit fly.

Question 22.4

List the three major classes of segmentation genes and outline the function of each.

Question 22.5

What role do homeotic genes play in the development of fruit flies?

Section 22.3

Question 22.6

How do class A, B, and C genes in plants work together to determine the structures of the flower?

Section 22.4

Question 22.7

What is apoptosis and how is it regulated?

Section 22.6

Question 22.8

Explain how each of the following processes contributes to antibody diversity.

  • a. Somatic recombination.
  • b. Junctional diversity.
  • c. Hypermutation.

Question 22.9

What is the function of the MHC antigens? Why are the genes that encode these antigens so variable?

For more questions that test your comprehension of the key chapter concepts, go to for this chapter.