AeroLab Reading room

Biology / IGCSE

Reproduction and development

Asexual reproduction produces offspring without gamete fusion and commonly preserves the parent’s genotype apart from mutation.

Learning objectives

The big idea

Asexual reproduction produces offspring without gamete fusion and commonly preserves the parent’s genotype apart from mutation. Sexual reproduction combines genetic material from gametes and usually generates variation.

Flower structures support pollen transfer and fertilisation, followed by seed and fruit development. Human reproduction involves specialised gametes, fertilisation and development in the uterus; the placenta exchanges materials without normally mixing maternal and fetal blood directly.

Worked example

A model produces 6 new plants from each of 4 parent plants. How many new plants form?

Follow the solution

Multiply four parents by six offspring each: 4×6=24.

Investigate and explain

Using the worked example as supplied data, predict the effect of changing one condition. Draw a labelled model, record your reasoning and identify a variable that would need controlling. No human, animal or microbial experiment is required.

No exact PhET model is claimed for this topic. Use diagrams and supplied-data reasoning instead.

Open the interactive investigation

Check your understanding

1. What is pollination?

  1. Fusion of gamete nuclei
  2. Growth of an embryo
  3. Transfer of pollen to a stigma
Check the answer and reasoning

Transfer of pollen to a stigma

Pollination precedes possible fertilisation and is a different process.

2. A model produces 6 new plants from each of 4 parent plants. How many new plants form?

  1. 24
  2. 10
  3. 2
Check the answer and reasoning

24

Multiply four parents by six offspring each: 4×6=24.

3. Are offspring of sexual reproduction normally genetically identical?

  1. Yes
  2. No
  3. Only with two parents
Check the answer and reasoning

No

Meiosis and fertilisation combine alleles in different ways, producing variation.