AP BIOLOGY

Detailed explanation-1: -You might notice that in hot weather, you only produce small volumes of urine as the body is fighting to conserve water. If water is in excess, ADH levels are reduced limiting the amount of water resorbed back into the blood but increasing the volume eliminated in the urine.

Detailed explanation-2: -During summer when the surrounding temperature is high, we lose water in the form of sweat, direct evaporation considerably. Hence kidneys retain water for maintaining fluidity of the blood and less urine is formed.

Detailed explanation-3: -In summer more water loss from the body occurs in the form of sweat. To compensate for the water loss, the nephrons in the kidney reabsorb water more efficiently (i.e. more amount of water is reabsorbed by the kidneys) leading to concentrated urine. Hence, urine is slightly thicker in summer than in winter.

Detailed explanation-4: -During exercise and heat stress, both glomerular filtration and renal blood flow are markedly reduced, resulting in decreased urine output. Therefore, when fluids are over consumed during exercise (hyperhydration), there may be a reduced ability to produce urine to excrete the excess volume.

Detailed explanation-5: -Kidney is able to reduce the water content of urine produced on a hot day by means of action of diuretic hormone. Explanation: Diuretic hormone controls the blood pressure in blood vessels and hence controls the water in urine by absorbing water in urine. Thus water in urine is reduced.