Describe the structural features of a sperm cell and explain how each feature is related to its function in sexual reproduction.

Cambridge International IGCSE Biology (0610) — 16.2 Sexual reproduction · Describe · 4 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

Model answer (4 marks)

The sperm cell has a
1. haploid nucleus in the head – it carries half the chromosome number, so fertilisation restores the diploid set.
2. an acrosome over the nucleus – it releases enzymes that digest the jelly coat of the egg, allowing penetration.
3. a midpiece packed with mitochondria – the ATP produced powers the flagellum.
4. a flagellum (tail) – it propels the sperm towards the egg.

Examiner tips

Use the exact terms (haploid nucleus, acrosome, midpiece, flagellum).
Show the link between each structure and its function – this earns the full 4 marks.
Keep the answer concise – 4 short points is ideal for 4 marks.

Common mistakes

Confusing the nucleus with the acrosome or omitting the acrosome.
Failing to mention that the mitochondria are in the midpiece or that the flagellum provides motility.

Mark scheme (4 marks)

The sperm cell has a haploid nucleus (in the head), which means it carries half the chromosome number so that fertilisation restores the full diploid chromosome number.
The midpiece contains many mitochondria, which provide energy (from respiration) for the movement of the flagellum / tail.
The flagellum (tail) allows the sperm cell to swim / move towards the egg cell.
The head contains an acrosome, which releases enzymes to digest / penetrate the jelly coat of the egg cell, allowing fertilisation to occur.

Key terms in this question

sperm cell