CAIE A-Level Biology AS 5.1 Replication and Division Questions

Practise CAIE AS Biology 5.1 by tracing the mitotic cell cycle and connecting chromosome structure, stem-cell replacement and uncontrolled division to tissue growth and tumours.

Exam points

Label chromosome diagrams with DNA, histones, sister chromatids, centromeres and telomeres.
Explain how mitosis makes genetically identical daughter cells for growth, repair, replacement and asexual reproduction.
Order G1, S and G2 interphase, mitosis and cytokinesis; connect S phase DNA replication to chromosome number.
Explain how telomeres protect genes at chromosome ends during replication and how telomerase affects shortening.
Describe how stem-cell self-renewal and differentiation support tissue replacement and repair.
Explain how mutations or failed cell-cycle control can cause uncontrolled division and tumour formation.

Covered syllabus points

5.1.1—Chromosome structure and telomeres 5.1.2—Importance of mitosis 5.1.3—Mitotic cell cycle 5.1.4—Telomeres 5.1.5—Stem cells 5.1.6—Tumour formation

[Maximum number: 1]

During sperm formation in mammals, part of the structure of each chromosome is replaced with proteins called protamines. This replacement allows the DNA to be packaged much more densely than would otherwise be possible.

Which part of the chromosome is replaced by protamines?

centromeres

chromatids

histones

telomeres

[Maximum number: 1]

Which diagrams show roles of mitosis?

1, 2, 3 and 4

1, 2 and 3 only

1 and 2 only

3 and 4 only

[Maximum number: 1]

The contents of a daughter cell are compared to the parent cell after one cell cycle.
Which row is correct?

number of chromosomes

volume of cytoplasm

length of telomeres

increases

remains the same

decreases

increases

decreases

remains the same

decreases

All question bank results loaded

Covered syllabus points

Question 1

Question 2

Question 3