What this topic covers
Topic 3: Genetics has 3 subtopics:
- Reproduction
- Cell division
- Variation and evolution
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GCSE Edexcel Higher Combined Science Biology · Topic 3 of 9
Topic 3: Genetics – GCSE Edexcel Higher Combined Science Biology revision notes
Choose a subtopic. Reproduction, DNA, inheritance, variation and genetics. 16 lessons in 3 subtopics.
Revise Topic 3: Genetics for GCSE Edexcel Higher Combined Science Biology, including Reproduction and Cell division. 16 lessons across 3 subtopics.
16
Lessons
3
Subtopics
Topic 3: Genetics lessons by subtopic
16 lessons, grouped by subtopic.
Reproduction
- Gametes in Sexual Reproduction
- Sexual vs Asexual Reproduction and Cell Division
- What is Meiosis?
- Fertilisation and Development
- DNA Structure and the Genome
- Applications of Genome Research
- Genetic vocabulary and basic inheritance (Part 1/2)
- Genetic vocabulary and basic inheritance (Part 2/2)
- Genetic crosses and Punnett squares
- Multiple gene inheritance
- Understanding Inherited Disorders
- Ethical Issues in Embryo Screening
- Sex Chromosomes and Genetic Crosses
Cell division
Variation and evolution
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Frequently asked questions
What is Topic 3: Genetics?
Reproduction, DNA, inheritance, variation and genetics. 16 lessons in 3 subtopics.
How many chromosomes do humans have?
Human body cells have 46 chromosomes arranged in 23 pairs. The Chromosomes, DNA and Genes notes cover this in full.
What is a gene?
A gene is a specific section of a DNA molecule that codes for a particular characteristic. The Chromosomes, DNA and Genes notes cover this in full.
What is an allele?
An allele is a different version of the same gene that controls the same characteristic but may produce different traits. The Genetic vocabulary and basic inheritance (Part 1/2) notes cover this in full.
What are gametes?
Gametes are specialised reproductive cells that contain half the normal number of chromosomes (haploid). The Gametes in Sexual Reproduction notes cover this in full.
What is a genome?
A genome is the entire genetic material of an organism. The DNA Structure and the Genome notes cover this in full.
What is a gamete?
A gamete is a reproductive cell, a sperm or egg, that contains half the normal number of chromosomes. The Genetic vocabulary and basic inheritance (Part 1/2) notes cover this in full.
What is meiosis?
Meiosis is a type of cell division that occurs in reproductive organs to produce gametes. The What is Meiosis? notes cover this in full.
What is the difference between haploid and diploid?
Haploid cells contain one complete set of chromosomes (n), as in gametes like sperm and egg cells, with n = 23 in humans. The Fertilisation and Development notes cover this in full.