The Master chemists of our body are the kidneys. Justify.

i) Kidneys filter all chemicals in the body.

ii) Kidneys maintain the chemical composition of blood.

iii) Kidneys eliminate all chemicals absorbed by the body.

iv) Kidneys store the chemicals accumulated in the body.

Fill in the empty boxes with suitable answers with respect to the valves of a mammalian heart.

Any change in the lifestyle, the food habits and the body form of an organism in order to make it comfortable in the environment / habitat, is called adaptation. Identify the suitable adaptation given below against each mammal.

i) conservation of body heat in large marine mammals like whale (Jaws are modified into baleen plates / Forelimbs are modified into flippers /

Fat is deposited in subcutaneous tissue.)

ii) Locating food source by bats-( Forelimbs are modified into wings / Hanging upside down using legs / Production of sounds and detection of the echo)

Observe the chart depicting the structure of a nephron.

i) Mention the structures A to F

ii) Explain the main function of a nephron.

With a suitable diagram, describe the structure and functions of the human heart.