Selective Breeding Compared with Other Techniques — Selective Breeding | IGCSE Biology

Exam Frequency Analysis

Past paper frequency (2018 to 2024)

This topic accounts for approximately 9% of your exam marks.

stable

Medium

Stable9%

Selective breeding vs natural selection comparisons and examples appear across most papers.

Selective breeding is one of several ways humans have developed to produce useful plants and animals. The full picture for the IGCSE syllabus includes:

Technique	What it does	Speed	Genetic variation in offspring
Selective breeding (this topic)	Bring together desirable alleles already present in the species, generation by generation	Slow (many generations)	Some (offspring inherit a mix from two parents)
Tissue culture / cuttings (this topic + topic 12)	Make many genetically identical clones of a chosen plant	Very fast	None (clones)
Genetic engineering (topic 18)	Insert specific genes from another species directly into an organism's DNA	Fast at the lab stage	None (precise control)
Cloning of animals (topic 18)	Make genetically identical copies of a chosen animal	Fast at the lab stage but technically demanding	None (clones)

Each technique has its place:

Selective breeding is the traditional approach, slow but reliable, useful when many small improvements need to combine
Tissue culture is best when a parent plant already has all the qualities you need
Genetic engineering is best when you need a specific feature (e.g. a particular protein) that does not exist in the species
Cloning is best when you have one outstanding individual whose exact genetic makeup you want to preserve

These topics will all come together in topic 18, which covers genetic engineering and cloning in detail.