In living organisms during respiration which of the following products are not formed if oxygen is not available?

1. Carbon dioxide + Water
2. Carbon dioxide + Alcohol
3. Lactic acid + Alcohol
4. Carbon dioxide + Lactic acid

The correct statements with reference to single celled organisms are:

(i) Complex substances are not broken down into simpler substances.

(ii) Simple diffusion is sufficient to meet the requirement of exchange of gases.

(iii) Specialised tissues perform different functions in the organism.

(iv) Entire surface of organism is in contact wih the environment for taking in food.

1. (i) and (iii)
2. (ii) and (iii)
3. (ii) and (iv)
4. (i) and (iv)

Which of the following statements are correct in reference to the role of A (shown in the given diagram) during a breathing cycle in human beings?

(i) It helps to decrease the residual volume of the air in lungs.

(ii) It flattens as we inhale.

(iii) It gets raised as we inhale.

(iv) It helps the chest cavity to become larger.

1. (ii) and (iv)
2. (iii) and (iv)
3. (i) and (ii)
4. (i), (ii) and (iv)

Which one of the following conditions is true for the state of stomata of a green leaf shown in given diagram?

1. Large amount of water flows into the guard cells.
2. Gaseous exchange is occurring in large amount.
3. Large amount of water flows out from the guard cells.
4. Large amount of sugar collects in the guard cells.