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

What are the differences between aerobic and anaerobic respiration? Name some organisms that use the anaerobic mode of respiration.

Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms?

What are the common features of the respiratory organs in aquatic and terrestrial animals?

Name the cell organelle in which the breakdown of pyruvate to give carbon dioxide,water,and energy takes place.

Which of the following statements is (are) correct?
$(i)$ Pyruvate can be converted into ethanol and carbon dioxide by yeast.
$(ii)$ Fermentation takes place in aerobic bacteria.
$(iii)$ Fermentation takes place in mitochondria.
$(iv)$ Fermentation is a form of anaerobic respiration.