The activity of the kidneys is controlled by hormones and by the
a. volume of nutrients.
c. composition of the blood.
b. volume of filtrate.
d. composition of the urine.

The activity of the kidneys is controlled by hormones and by the "composition of the blood.".

If the blood pressure drops too low, the kidneys may experience issues in working properly. On the off chance that this circumstance happens, the kidneys discharge renin. This encourages the kidneys to filter the blood legitimately. The direction of water reabsorption is controlled by the mind, utilizing a hormone called ADH, or antidiuretic hormone. The hypothalamus recognizes the grouping of water in the blood and body liquids. At the point when these liquids get too thick, the hypothalamus flags the pituitary organ to discharge ADH into the circulatory system. At the point when ADH achieves the modest vessels in the kidney, it changes the capacity of the films of the renal tubules to hold water, enabling more water to be reabsorbed and monitored by the body. Subsequently, affected by ADH, the kidney creates less urine. At the point when the hypothalamus identifies enough water in body liquids, or excessively, it quits creating ADH and the renal tubules clutch a greater amount of the water that filter from the glomerulus, in this manner discharging a higher volume of urine.

c. composition of the blood.

Explanation:

Kidneys are blood filters that periodically clean it extracting waste, which is expelled in form of urine. Blood carries a lot of things, like nutrients, minerals like sugar and salt. So, when the blood pass through the kidneys waste is removed, salt, water and minerals are regulated if needed, and electrolytes levels are regulated.

In addition, the blood has to have a specific pressure to make kidneys work. If blood pressure is too low, a part or whole kidneys will die, starting by a failure in their functioning.

Smoking damages the respiratory system by inhalation of a foreign substance, that is absorbed and residue is left behind on our lungs sponge like substance. the gas that is inhaled also increase your blood pressure and dilates your blood vessels. also the process of inhaling and exhaling the smoke it causes irritation to the throat and mouth. smoking can cause lung cancer and other respiratory and circulatory diseases.