With the help of one example, explain the phenomena of co-dominance and multiple allelism in human population.
Write the scientific name of the fruit-fly. Why did Morgan prefer to work with fruit-flies for his experiments? State any three reasons.
The scientific name of the fruit-fly is - Drosophila melanogaster.
Morgan preferred to work with fruit-flies for his experiments because of the following reasons:
i. They could be grown on simple synthetic medium in the laboratory.
ii. They completed their life cycle in about two weeks and a single mating could produce a large number of progeny flies.
iii. It had many types of hereditary variations that could be seen with low power microscopes.
Linkage or crossing-over of genes are alternatives of each other. Justify with the help of an example.
Explain the significant role of the genus Nucleopolyhedrovirus in an ecological sensitive area.
How have transgenic animals proved to be beneficial in:
(a) Production of biological products
(b)Chemical safety testing.
Describe the mutual relationship between fig tree and wasp and comment on the phenomenon that operates in their relationship.
Construct an age pyramid which reflects an expanding growth status of human population.
Make a list of any three out breeding devices that flowering plants have developed and explain how they help to encourage cross-pollination.