Question

This is true for excretion in humans:
A. Glucose and amino acids are reabsorbed in PCT by simple diffusion
B. DCT is impermeable to water
C. On the average, 25−30 gm of urea is excreted per day
D. Maximum reabsorption occurs in the loop of Henle's

Answer 1

Hint: Secondary active transport reabsorbs glucose and amino acids in PCT. DCT reabsorbs sodium, and chloride ions. DCT is water impermeable. Maximum reabsorption occurs inside the PCT.

Complete step by step answer:
Excretion is the process by which animals get rid of waste products. This process usually occurs through the urinary tract and the digestive tract. The urinary system excretes nitrogenous wastes from the body in a liquid form. The kidneys filter blood to remove nitrogenous wastes, and then these wastes are excreted through urine. The digestive system excretes solid wastes from the body in a solid form. The intestines absorb nutrients from food, which are then broken down by bacteria in the large intestine, producing solid wastes excreted through faeces.
Human urine comprises 95 percent water, 2.5 percent urea, and 2.5 percent miscellaneous waste. Because urea is the most common excretory waste, humans are classified as ureotelic; and approximately 25-30 g of urea is expelled every day.
For this reason, the right answer is both option B and C.

Note: The kidneys are the major organs of excretion. The kidneys filter the blood, removing excess water and waste products, including urea. The average person excretes about 25-30 grams of urea per day. Urea is a nitrogen-containing compound that is the main component of urine. The average amount of urea excreted per day can vary from person to person and depends on age, gender, diet, and health.