When we breathe out,why does the air passage not collapse?

$(a)$ $A$ product is formed in our muscles due to the breakdown of glucose when there is a lack of oxygen. Name the product and also mention the effect of the build-up of this product.
$(b)$ Differentiate between fermentation in yeast and aerobic respiration on the basis of end products formed.

$(a)$ Name the following:
$(i)$ Part in which urine is produced.
$(ii)$ Part which stores the urine.
$(iii)$ Part which connects $(i)$ and $(ii)$.
$(iv)$ Part from which urine is passed out.
$(b)$ Name the factors on which the amount of water reabsorbed along the tubular part of the nephron depends.

How do autotrophs obtain $CO_{2}$ and $N_{2}$ to make their food?

Match Group $(A)$ with Group $(B)$:

Group $(A)$	Group $(B)$
$(a)$ Autotrophic nutrition	$(i)$ Leech
$(b)$ Heterotrophic nutrition	$(ii)$ Paramecium
$(c)$ Parasitic nutrition	$(iii)$ Deer
$(d)$ Digestion in food vacuoles	$(iv)$ Green plant

Is 'nutrition' a necessity for an organism? Discuss.