Inheritance & EvolutionTopic Summary

Knowledge Organiser

Part of Selective Breeding · GCSE GCSE Biology revision

This topic summary covers Knowledge Organiser within Selective Breeding for GCSE Biology. Artificial selection and selective breeding techniques It is section 10 of 11 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 10 of 11

Practice

28 questions

Recall

20 flashcards

Knowledge Organiser

Key Terms

Selective breeding — humans choose which organisms breed
Artificial selection — another name for selective breeding
Inbreeding — breeding between closely related individuals
Gene pool — all alleles in a breeding population
Inbreeding depression — reduced fitness from narrow gene pool
Desired trait — characteristic being selected for

SSBR Steps

Select — parents with desired trait
Separate — use them as breeding stock
Breed — cross them together
Repeat — select best offspring, breed again
Over many generations — desired allele frequency increases

Examples

Wheat — disease resistance, high yield
Dairy cows — high milk yield
Dogs — temperament, size, working ability
Roses — petal size, colour, fragrance

Disadvantages

Reduces genetic variation (narrows gene pool)
Inbreeding depression — harmful recessive alleles expressed
Population vulnerable to disease outbreaks
Animal welfare issues (e.g., flat-faced dogs)
No new alleles created — only existing ones selected

Common Mistakes

Omitting "over many generations": This phrase appears in virtually every mark scheme — without it, you will likely lose a mark when describing the selective breeding process.
Saying selective breeding creates new genes: Selective breeding only selects from variation that already exists — it does not introduce new alleles. This is the key difference from genetic engineering.
Vague disadvantage answers: "It reduces genetic variation" alone often scores no marks — explain the consequence: if all individuals have similar alleles, a disease that overcomes one individual's immunity will affect the entire population.
Describing it as fast: Selective breeding takes many generations and is a slow process — this is a disadvantage compared to genetic engineering, which can achieve results in one generation.

Revise this topic interactively on PrepWise — self-test mode, tap-to-reveal definitions, and Common Mistakes from examiners.

Try the interactive Knowledge Organiser — free →

Keep building this topic

Read this section alongside the surrounding pages in Selective Breeding. That gives you the full topic sequence instead of a single isolated revision point.

Exam Focus Exam Tips: Selective Breeding What is Selective Breeding?Examples of Selective Breeding

Practice Questions for Selective Breeding

What is selective breeding?

A. The random mating of organisms in the wild
B. The process of choosing organisms with desired traits to breed together
C. The genetic modification of organisms using DNA technology
D. The natural selection of organisms by environmental pressures

1 markfoundation

Explain how selective breeding has been used to develop modern wheat varieties with higher yields.

4 marksstandard

Quick Recall Flashcards

Describe the process of selective breeding.

1. Choose parents that show the desired characteristic. 2. Breed them together. 3. Select offspring that best show the characteristic. 4. Repeat over many generations. Over time the desired trait becomes more common in the population.

Give three examples of selective breeding.

1. Dogs — bred for specific traits (speed in greyhounds, herding in border collies, guiding in labradors). 2. Cattle — bred for high milk yield or increased meat production. 3. Wheat — bred for disease resistance, higher yield, and shorter stems (less likely to fall over).

28 questions on Selective Breeding — practise free

Instant marking, adaptive difficulty, and 20 spaced repetition flashcards. Free until your GCSEs.

Try PrepWise Free

Exam Focus

Exam Tips: Selective Breeding