Biology A-Level
plasmids
What plasmids means in Biology A-Level, as defined for AQA.
Definitions of plasmids
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Reference: AQA
Small circular loops of DNA separate from the main circular DNA molecule, carrying genes not essential for survival and replicating independently of it.
Small, separate circles of DNA holding extra genes such as those for antibiotic resistance, but not the cell's main DNA molecule.
Topics that use plasmids
- DNA, genes and chromosomes (AQA A-Level)
- Structure of prokaryotic cells and of viruses (AQA A-Level)
Related terms
- alleles
- attachment proteins and host receptors
- base sequence
- capsule
- chromatin
- circular organelle DNA
- crossing over
- degenerate code
Using plasmids in the exam
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