IB Biology SL 2.1.2 Cytokinesis Question Bank
Practise IB Biology SL 2.1.2 by describing cytokinesis and how it separates daughter-cell cytoplasm.
- Syllabus
- First assessment 2025
- Course
- Biology SL
- Level
- SL
Practise IB Biology SL 2.1.2 by describing cytokinesis and how it separates daughter-cell cytoplasm.
Both the genome and the environment of an organism affect its growth and development. Variation between individuals of a species can be continuous or discrete (discontinuous). Mitosis produces identical cells for growth and meiosis allows for variation.
The micrographs show onion and whitefish cells in mitosis.

The process of cytokinesis is occurring in the whitefish embryo cells. Explain how cytokinesis occurs in this animal cell.
a. (plasma/cell) membrane pulled inwards
OR membrane/cell pinched together (around the equator of the cell);
b. (by) ring of proteins / contractile ring/proteins
OR
(by) actin and myosin;
c. cytoplasm is split / cell divides;
d. organelles are distributed between the two cells
OR
organelles are pulled by microtubules to opposite poles;
a. Accept OWTTE, including cleavage furrow or an invagination forming.
b. Do not accept proteins unqualified.
b. Both actin and myosin required for the mark in the second alternative.
c. Accept OWTTE.
2
Marking guidance:
max