The transfer of pollen grains from anthers (male sexual parts) of a flower to the stigma part of the pistil (female sexual part) is known as pollination. Pollination is done by insects, birds, wind and water.
Pollination can occur in two ways:
1. Self pollination: When the pollen grains from the anther of a flower are transferred to the stigma of the same flower or another flower on the same plant, it is called self pollination.
2. Cross pollination: When the pollen grains from the anther of a flower on one plant are transferred to the stigma of a flower on another similar plan it is called cross pollination.
When a pollen grain falls on the stigma of the carpel, it grows a pollen tube downwards through the style towards the female gamete in the ovary. A male gamete moves down the tube. When the pollen tube enters the ovule, its tip bursts open and male gamete comes out of the pollen tube and combings with the nucleus of the female gamete and forms zygote. This process is known as fertilization.

(a)

(b) The pollen tube moves through the style and reaches the ovule. It carries male gerrn cells to the ovule for fertilisation.
(c) (i) Ovules develops into seed.
(ii) Ovary develops into fruit.

No this is because when there is a change in any species, there is change only in a part or a few members of the species population.

A trait (or characteristic) of an organism which is 'not inherited' but develops in response to the environment is called an acquired trait.
The acquired traits of an organism cannot be passed on to its future generations.
For example, 'low weight' of beetle, 'cut tail' of a mouse. Changes brought in the non-reproductive tissues cannot be passed on to the DNA of the germ cells. So the experiences of an individual during its lifetime cannot be passed on to its progeny. Thus acquired characters of an individual cannot be inherited.

The position of man is at the apex of most food chains as he is an intelligent organism and can take any advantageous position by manipulation.

Light, water, gravity, touch and chemical substance

The cross in which just two contrasting characters are studied is called monohybrid cross. Mendel did monohybrid cross for his first experiment. He selected a pair of contrasting characters. For example cross between tall plants and short plants. IT represents the genotype of tall plant and tt represents the genotype of short plants. In the F2 generation, all plants were tall but their genotype was Tt; which means they were not pure tall plants. This could be established by the appearance of the character of shortness in the F2 generation; in which most of the plants were tall and some of the plants were short. This experiment showed that the character of shortness was recessive in F1 generation and hence could not be observed. The ratio of number of tall plants to that of short plants in F2 generation was 3 : 1.

If leaves of a plant were covered with aluminium foil, then leaves may not get sunlight, which is the basic requirement for all the processes occurring in the plant. As a result, no photosynthesis will occur, so no glucose will be made. Also, no respiration will take place as no oxygen will be taken in due to blocked stomata. No transpiration will occur, so there would be no upward movement of water or minerals from the soil as there will be no transpirational pull. Temperature regulation of leaf will be affected.

(a): Both A and R are true and R is correct explanation of the assertion

(a): Hospital waste contains a lots of germs so it should not be disposed openly. Burning the waste kills the germs and disposes the waste in proper way.

(i) (b): In the given figures B represents artery that carry blood away from the heart to different organs.
(ii) (c): In the given figures, A represents vein. Veins bring blood from different body parts to the heart. The flow of blood in veins is not so fast because the blood in veins is under low pressure. Veins possess valves which prevent backward flow of blood.
(iii) (a): Veins carry deoxygenated blood with single exception, i.e., pulmonary vein. Arteries carry blood from heart towards the organ.
(iv) (d)
(v)  (a)