Biology 111B

Study Questions 17: Genetic control of development

 

1. What does the term "differentiation" mean?

 

2. What are three broad categories of genes that function in differentiation? In what order do they act in Drosophila?

 

3. Why do we care about how an insect like Drosophila develops?

 

4. What is induction? Give an example of how it works.

 

5. The establishment of a dorsal-ventral axis in a developing embryo is a crucial aspect of… (only one correct answer)

a. transcriptional regulation

b. pattern formation

c. cell division

d. induction

 

6. Cell differentiation involves… (circle all correct answers)

a. the action of tissue specific transcription factors

b. the action of maternal proteins in the egg/embryo

c. the selective loss of certain genes from the DNA

d. the action of maternal DNA in the egg/embryo

 

7. Select the correct statement(s) concerning the bicoid gene and its role in Drosophila development. (only one correct answer)

a. Defects in the gene result in embryos with heads at both ends.

b. Maternal bicoid RNA is deposited within the unfertilized egg and translated only after fertilization.

c. The bicoid protein is made by the mother.

d. The production of bicoid protein and its diffusion to adjacent cells demonstrates induction.

 

8. Homeotic genes… (only one correct answer)

a. encode transcription factors that control the expression of genes responsible for initiating specific anatomical structures

b. are found only in Drosophila and other insects

c. specify the anterior-posterior axis for the embryo

d. create the basic segments of the embryo

 

9. How does the term "developmental cascade" describe the actions of transcription factors during development?

 

10. Given the function of the bicoid gene product, if large amounts of bicoid protein were injected into several areas of a Drosophila egg, what would be the outcome?