Natality	Mortality
The total number of live births per 1000 people of population per year is called birth rate or natality.	The total number of deaths per 1000 people of population per year is called death rate or mortality.

Give the biological/technical terms for the following:
(i) A membrane which allows the passage of molecules selectively.
(ii) The suppressed allele of a gene.
(iii) Structure that carries visual stimuli from retina to the brain.
(iv) WBCs squeeze through the walls of the capillaries into the tissue.
(v) Protective coverings located round the human brain and spinal cord.
(vi) Eye lens losing flexibility resulting in a kind of long sightedness in elderly people.
(vii) Hormones which stimulate other endocrine glands to produce their specific hormones.
(viii) The phase in the menstrual cycle in which the remnant of follicle in the ovary turns to Corpus luteum.
(ix) Statistical study of human population.
(x) Artificially introducing weakened germs or germ substance into the body for developing resistance to a particular disease.

Given below is the diagram of a cell as seen under the microscope after having been placed in a solution:
(i) What is the technical term used for the state/condition of the cell given above ?
(ii) Give the technical term for the solution in which the cell was placed.
(iii) Name the parts numbered 1 to 4.
(iv) Is the cell given above a plant cell or an animal cell? Give two reasons in support of your answer as evident from the diagram.
(v) What would you do to bring this cell back to it original condition?