Genetics
Contents
Key Stage 4
Meaning
Genetics is the study of inheritance and genes.
The Development of Genetics
- Genetics was gradually discovered over a large period of time.
- The first evidence for genetics came when an Austrian Monk named Gregor Mendel began experimenting with pea plants. Mendel noticed that when certain varieties of pea plants were crossed (wrinkled vs smooth peas) these traits were inherited in predictable ways.
- In the late 19th century chromosomes were first observed in cells that were undergoing cell division.
- By the early 20th century scientists had noticed that Mendel's prediction that there were units of inheritance matched the behaviour of chromosomes during cell division.
- Scientists did not know what genes were made of until Rosalind Franklin and Maurice Wilkins investigated the structure of DNA using 'X-ray Diffraction' and then Francis Crick and James Watson built 3d models which showed the double helix shape of DNA.
- This gave rise to the development of 'Gene Theory' which suggested genes were made of DNA and that they coded for the synthesis of specific proteins.
References
AQA
- Genetics, pages 132, 195, 236-69, GCSE Biology; Student Book, Collins, AQA
- Genetics, pages 194-255, GCSE Biology; Third Edition, Oxford University Press, AQA
Edexcel
- Genetic; diagrams, pages 28, 29, GCSE Combined Science; The Revision Guide, CGP, Edexcel
- Genetic; diagrams, pages 38-41, GCSE Biology; The Revision Guide, CGP, Edexcel
- Genetic; engineering, page 37, GCSE Combined Science; The Revision Guide, CGP, Edexcel
- Genetic; engineering, page 52, GCSE Biology; The Revision Guide, CGP, Edexcel
- Genetic; variants, page 35, GCSE Biology; The Revision Guide, CGP, Edexcel
- Genetic; variation, page 30, GCSE Combined Science; The Revision Guide, CGP, Edexcel
- Genetic; variation, page 42, GCSE Biology; The Revision Guide, CGP, Edexcel
- Genetics, pages 64-65, GCSE Combined Science, Pearson Edexcel
OCR