IBDP Biology Question Analysis Topic: Biology - Short Questions
Exam Questions:
1) State how has Agrobacterium tumifaciens been made a useful cloning vector to transfer DNA to plant cells.
2) State the cause of accelerated eutrophication.
Answers:
For IBDP Biology, you should know:
1) Plant pathogen Agrobacterium tumefaciens is most effective as a plant genetic engineer. In plants, it causes the formation of crown gall. Ti, a plasmid that causes tumours, is a useful cloning vector in plants.
It can be altered with new DNA, and the plasmid introduces a piece of DNA that turns healthy plant cells into cancerous ones.
The introduction of the Ti plasmid into a plant helps it to produce its own nutrient machinery because it contains genes for the synthesis of auxin and the hormone cytokinin.
2) Ageing of a water body that happens due to nutrient enrichment of its water is known as accelerated eutrophication. It might be artificial or natural.
Causes:
- Eutrophication is caused by an algal bloom that is brought on by runoff of fertilizers from nearby fields into the water body.
- The temperature and BOD of the water body are raised by sewage and industrial effluents, which increases biological activity and causes algal blooms.
Work hard for your IBDP Biology examination!
End of analysis. Great!
