Which of the following actions does not occur during exhalation in man?

The diagram above is an illustration of the urinary tubule in a mammal. Which of the following substances is found in the part labelled II only?

The diagram above is an illustration of the urinary tubule in a mammal. The part which contains lowest concentration of urea is labelled

The diagram above is an illustration of the urinary tubule in a mammal. Which of the following substances is greater in concentration in the part labelled IV when compared to that part labelled I?

Deamination of amino acids in the liver produces