To identify the organs responsible for urea production and elimination in mammals, we need to consider the specific physiological roles:
Therefore, the two important organs associated with the production and elimination of urea in mammals are the liver and the kidneys.
| Group I | Group II |
| P. 17-$\beta$ estradiol | 1. Arachidonic acid |
| Q. Thromboxane A2 | 2. Tyrosine |
| R. Epinephrine | 3. $\beta$-carotene |
| S. Retinoic acid | 4. Cholesterol |
Which of the following statements are TRUE for respiration?
P. The conversion of one molecule of pyruvate to three molecules of $CO_2$ generates four molecules of NADH
Q. Fructose 6-phospate is the principal substrate for glycolysis
R. The oxidation of glucose 6-phosphate to 6-phosphogluconate is the first step in the oxidative pentose phosphate pathway
S. The mitochondrial 'alternative oxidase' provides an alternative pathway for transfer of electrons from ubiquinone to oxygen utilizing proton pumping complex of the respiratory chain