NATIONAL OPEN UNIVERSITY OF NIGERIA

UNIVERSITY VILLAGE, PLOT 91, CASDASTRAL ZONE, NNAMDI AZIKIWE EXPRESS WAY, JABI, ABUJA.
FACULTY OF SCIENCES
MARCH/APRIL 2015 EXAMINATION

COURSE CODE:                  BIO 301

COURSE TITLE:                 GENETICS II

TIME ALLOWED:               2 Hours

INTRUCTION: Answer question ONE (1) and any other THREE (3) questions

1a.Explain how genes determine sex? (4 marks)

b. Describe the structure of a virus. (7 marks)

c. List the characteristic features of haploid plants. (6 marks)

d. How can you tell if there are any mutant colonies in a culture? (8 marks)

2a. Define genetic transfer. (1 mark)

  b. Describe the antibodies and blood antigens relationships in ABO blood group. (6 marks)

  c. Account for the mode of occurrence of different inversions you know. (8 marks)

3a. List the general steps of the lytic cycle. (5 marks)

 b. Describe the mechanisms of balancing selection. (3 marks)

 c. Describe the various methods by which polyploidy can be induced. (7 marks)

4a. Enumerate the role of structural chromosomal aberrations in plant breeding. (5 marks)

  b. Explain the defects of abundant and structural proteins. (10 marks)

 5a. What do you understand by the term paralogous? (3 marks)

 b. Write short notes on the following:

1. Gene recombination (4 marks)         
2. Gene transfer (4 marks)   
3. Frameshift mutation (4 marks)

6a. Outline the steps in specialized translocation. (5 marks)

 b. Polyploids are of significant effects. Discuss. (10 marks)