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 303

COURSE TITLE:                      GENERAL CYTOLOGY

TIME ALLOWED:                  2 Hours

INTRUCTION: ANSWER QUESTION 1 (COMPULSORY) AND ANY OTHER THREE QUESTIONS.

1. a. Three (3) major control checkpoints exist during the course of eukaryotic cell cycle. Mention these checkpoints. Explain any one of these checkpoints. 10marks

b. In a tabular form, make a brief comparism between RNA and Proteins. 15marks

2. a. Define the following terms:

1. Cytogenetics; 2marks
2. Cytology; 2marks and
3. Genetics. 2marks

          b. i. Mention the different types of Structural Chromosomal Variations.a 4marks

          ii. Define each of the mentioned structural chromosomal variations.  4marks

          c. i. What is Numerical Chromosomal Variation? 5marks

          ii. Mention the different types of numerical chromosomal variations. 6marks

3. a. Mention the general cytogenetic procedures synonymous to all cytogenetic techniques. 8marks

b. i. Define Karyotype. 2marks

ii. After Karyotyping, mention the observable characteristics in the chromosomes. 5marks

c. Outline the importance and applications of cytogenetics. 10marks

4. a. Mention the molecular composition of a cell. 5marks

b. State the functions/importance of protein in a living cell. 5marks

c. Mention the different types of Nucleic acids. 5marks

d. Outline the roles of the different types of nucleic acids. 10marks

5.  i. Mention the two major phase of cell cycle. 4marks

                      ii. Name the five stages of mitosis. 5marks

                      iii. Define the word “Embryology”. 2marks

4. Mention the stages of embryogenesis. 4marks
5. Explain briefly, the word “Diakinesis. 10marks

6. a. State the function(s) of the following parts of a Light Microscope (15marks):

1. Eye piece;
2. Body tube;
3. Objectives;
4. Diaphragm; and
5. Stage.

          b. State the advantages of a Phase Contrast Microscope. 4marks

          c. Define Darkfield Microscopy. 2marks

          d. Mention two advantages of an electron microscope. 4marks