21.1 Biotechnology and genetic modification
- Syllabus
- 0610–2026–2027
- Topic
- 21.1
- Level
- —
Learning objectives
21.1.1Bacteria are useful in biotechnology• State that bacteria are useful in biotechnology and genetic modification due to their rapid reproduction rate and their ability to make complex molecules21.1.2Discuss why bacteria are useful• Discuss why bacteria are useful in biotechnology and genetic modification, limited to: (a) few ethical concerns over their manipulation and growth (b) the presence of plasmids
Link bacterial features to biotechnology
Bacteria are useful in biotechnology and genetic modification because they reproduce rapidly and can make complex molecules.
| Feature | Why it is useful |
|---|---|
| rapid reproduction | a small starting culture quickly produces many bacterial cells, allowing fast large-scale production |
| ability to make complex molecules | bacteria can manufacture useful products rather than only simple raw materials |
The combined advantage is scale: rapid cell division creates many producers, and each cell can make the required complex molecule.
Rapid reproduction alone increases cell number; usefulness also depends on the cells producing the desired molecule.
Explain the ethical and plasmid advantages of bacteria
Bacteria offer two further advantages for biotechnology and genetic modification: few ethical concerns and the presence of plasmids.
| Advantage | Why it matters |
|---|---|
| few ethical concerns | manipulating and growing bacterial cultures generally raises fewer welfare concerns than manipulating animals |
| plasmids | these small circular DNA molecules can be removed, receive an inserted gene and be transferred back into a bacterium |
Once a useful gene is carried on a plasmid inside bacteria, the bacterial cells can copy the plasmid as they reproduce and use the gene to make its product.
A plasmid is a small circle of DNA, not the bacterium's main chromosome, nucleus or a mitochondrion.