Cell Division-Sampel Qs

Diagram shows the phases in a cell division in cell X. The phases are not in the correct sequence.

(a) (i) Name the type of cell division.
(ii) State an organ where this cell division takes place.

(b) State the number of chromosomes of cell X during phase P and phase U.

c) (i) State the name of each phase of the cell division in Table 3

Phase Name of the phase
P

Q

R

S

T

U

(ii) State the phase that brings about variation in organism. Explain your answer.

(d) Cell X is treated with a type of chemical that retards the function of centrioles. Explain what will happen to the chromosomal behavior in phase P.

Suggested Answer:

4(a) (i)Meiosis

(ii) Ovary // Testis

(b) 4 , 2

(c)(i)
Phase Name of the phase
P Anaphase I
Q Metaphase I
R Telophase I/ Prophase II
S Anaphase II
T Prophase I
U Telophase II

(c) (ii))Phase T/Prophase I
- Crossing-over occurs.
-Exchange of genetic material / segment of chromatid between members of homologous chromosomes.
-Daughter cells have different gene combination.

(d) The centrioles form spindle fibers to separate chromosomes (during anaphase).
-so the retarded centrioles will cause spindle fibres cannot be formed.
- (As a result) the chromosomes cannot pulled to the opposite poles.