Human Health and Disease — BIOLOGY STD 12 Science — Question

Write briefly the role of pollination in the growth and development in an angiosperm.

What is the source of hallucinogens? Why are they called as psychedelic drugs?

1. Name the Protozoan parasite that causes amoebic dysentery in humans.
2. Mention two diagnostic symptoms of the disease.
3. How is this disease transmitted to others?

A and B are the two different cloning vectors in two different bacterial colonies cultured in chromogenic substrate, Bacterial colonies with cloning vector A were colourless, whereas those with B were bluecoloured. Explain giving reasons the cause of the difference in colour that appeared.

The epithelial lining of the human intestine is considered a secondary lymphoid organ. Prove the validity of the statement.

List four causes of biodiversity loss.

Name the pioneer and the climax species in a water body. Mention the changes observed in the biomass and the biodiversity of the successive seral communities developing in the water body.

Explain any two methods of vector less gene transfer.

What is puffed up appearance of Idli/ Dosa due to which metabolic pathway is involved in it?

"Genes contain the information that is required to express a particular trait." Explain.