Just as $CO_{2}$ is removed from the blood in the lungs,nitrogenous wastes such as urea or uric acid are removed from blood in the liver.

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.

Mention the site of photosynthesis. List basic requirements for this process to occur.

Choose the correct statement that describes arteries.

$(a)$ Draw the structure of a nephron and label the following parts on it:
$(i)$ Renal artery
$(ii)$ Bowman's capsule
$(iii)$ Glomerulus
$(iv)$ Collecting duct
$(b)$ Name four substances in the initial filtrate which are selectively reabsorbed as the filtrate flows along the tubule.

Urine is stored in the urinary bladder until the pressure of the expanded bladder leads to the urge to pass it out through the urethra.