Human Health and Disease — BIOLOGY STD 12 Science — Question

How are morphine and heroin related? Mention the effect each one of them has on the human body?

Give a scientific term for the following sentences:

1. Total number of individuals of a species in an area.
2. A surgical procedure performed on males in which the vas deferens are cut and tied is known as:
3. A contraceptive device consisting of a small thimble-shaped cup that is placed over the uterus to prevent the entrance of spermatozoa.
4. Removal of gonads, often referring to the removal of male testes is called.

Thermal power plants are inevitable in an industrial and densely populated country like ours. What harm do they do to the environment? Also mention any precautions that could be taken to save our environment.

Woman have more responsibility than man in the reproductive process. Why? Explain.

What is census? Give India's population according to 1991 and 2001 census.

DDT content in the water of a lake that supplies drinking water to the nearby villages, is found to be 0.003 ppm. The kingfishers of that area are reported to have 2 ppm of DDT. Why has the concentration increased in these birds? What harm will this cause to the bird population? Name the phenomenon.

What is the ecological principle behind the biological control method of managing with pest insects ?

Which part in the male reproductive system stores sperms?

How is a continuous culture system maintained in bioreactors and why?

Why are predators considered prudent in nature?