IB Biology HL D2.1 Cell and Nuclear Division Questions
Practise IB Biology HL D2.1 by identifying cell-division stages, explaining meiosis outcomes and interpreting chromosome evidence.
- Syllabus
- First assessment 2025
- Course
- Biology HL
- Level
- HL
Exam points
- identify mitosis stages in micrographs and explain how sister chromatids separate
- compare cytokinesis examples, including equal division and unequal budding in yeast
- explain meiosis outcomes such as crossing over, non-disjunction and trisomy 21
Covered syllabus points
D2.1.1—Generation of new cellsD2.1.2—CytokinesisD2.1.3—Equal and unequal cytokinesisD2.1.4—Roles of mitosis and meiosisD2.1.5—DNA replication prerequisiteD2.1.6—Shared featuresD2.1.7—Phases of mitosisD2.1.8—Identification of mitosis phasesD2.1.9—Meiosis as reduction divisionD2.1.10—Down syndromeD2.1.11—Meiosis generates variationD2.1.12 (HL)—Cell proliferationD2.1.13 (HL)—Cell cycle phasesD2.1.14 (HL)—Cell growth during interphaseD2.1.15 (HL)—Cell cycle control by cyclinsD2.1.16 (HL)—Mutations in cell cycle genesD2.1.17 (HL)—Tumour differences
Question 1
[Maximum number: 1]
What describes nuclear division in stem cells?
A
Clonal selection
B
Mitosis
C
Cytokinesis
D
Meiosis
B
Question 2
[Maximum number: 8]
Eukaryotes are a diverse group of organisms, including animals and plants.
Compare and contrast the processes of mitosis and cytokinesis in animal and plant cells.
Similarities: [6 max]
a. (in both plants and animals) produces two genetically identical daughter cells;
b. maintains the chromosome number/genome of cell / produces diploid/2n cells;
c. used for generation of new cells/cell replacement/tissue repair/growth;
d. in prophase the chromatin/chromosome condenses/formation of chromatids/supercoiling of chromosomes;
e. supercoiling of DNA around histones (to form nucleosomes);
f. microtubules/microtubule motors to move chromosomes/chromatids;
g. in metaphase chromosomes align in equator of cell;
h. in anaphase separation of chromatids;
i. in telophase two nuclei/cells form / nuclear membrane/envelope reforms
OR
cytokinesis is the division into two cells;
Differences:
j. in animal cell centrosomes/centrioles facilitates the organization of the mitotic spindle/ spindle poles/microtubules;
Marking points for 8c continued on next page....
Marking guidance:
Max 6 for similarities.
Allow clearly annotated diagrams.
8 max
8c continued ....
8.
c
k. in plant cells spindle fibres attach to walls;
I. in animal cells, the plasma membrane is pulled inwards around the equator to form a cleavage furrow in cytokinesis
OR
in animal cells actin and myosin pinch cell membrane to split cytoplasm/cytokinesis;
m. in plant cells a cell plate forms (at the equator) to develop into the new cell wall to achieve cytokinesis
OR
in plant cell vesicles (containing pectin) assemble sections of membrane/cell wall (at/across the equator) to achieve splitting/cytokinesis;
Question 3
[Maximum number: 4]
The genome is the total of all the DNA in an organism, containing all the genetic information required for development and growth.
Distinguish between cell division by mitosis and by meiosis in eukaryote cells.
4
Marking guidance:
max
a.
b.
d.
e.
f.
g.
h.
maintains chromosome
maintains chromosome number/diploid;
number/diploid;
;
for growth/repair
;
in somatic cells
;
one division
;
no exchange of genetic material between chromosomes/crossing over;
;
results in two cells
;
only divides chromatids/
chromatids separate during
anaphase
genetically identical
;
All question bank results loaded