WAEC 2014 Biology · Question 4

The following events occur during mitosis in a cell: I. Chromatids separate; II. Chromosomes become visible…

Question

The following events occur during mitosis in a cell: I. Chromatids separate; II. Chromosomes become visible; III. Chromosomes align at the equator IV. Cytoplasm divides (Cytokinesis): The correct sequence of the events is

A.lll, ll,lV,l.
B.ll, lll, l,lV
C.ll, l, lll, lV
D.II, IV, I, III.

Answer: B. ll, lll, l,lV

Explanation written with AI and checked against the answer key

Analyze the question: You are asked to arrange four events of mitosis in the order they happen.

Concept: Mitosis runs through these stages: Prophase, Metaphase, Anaphase, Telophase (with cytokinesis at the end).

Matching each event to its stage:

II. Chromosomes become visible: Prophase. The chromatin condenses into visible chromosomes.
III. Chromosomes align at the equator: Metaphase. They line up on the metaphase plate.
I. Chromatids separate: Anaphase. The centromeres split and the chromatids are pulled to opposite poles.
IV. Cytoplasm divides (cytokinesis): Telophase. The cell divides into two daughter cells.

Correct sequence: II → III → I → IV

Checking the options:

A. III, II, IV, I: wrong, because chromosomes cannot align before they become visible.
B. II, III, I, IV: correct.
C. II, I, III, IV: wrong, because chromatids cannot separate before they align.
D. II, IV, I, III: wrong, because cytokinesis comes last.

Tip: Remember PMAT: Prophase (visible), Metaphase (middle), Anatomy... better: Anapahse (apart), Telophase (two cells). "Visible, Middle, Apart, Two" gives II, III, I, IV.

AI can make mistakes. Report anything that looks wrong.