Question

The main function of the loop of Henle is the reabsorption of water from the contents of renal tubules. In which of the following will the loop of Henle be poorly developed or even absent.
(A) Desert mouse
(B) Carnivorous bird
(C) Freshwater fish
(D) Garden bladder

Answer 1

Hint:Excretion is a process by which metabolic waste is eliminated from an organism. It can be carried out by the lungs, kidneys, and skin. In unicellular organisms, waste products are discharged directly through the surface of the cell. In higher organisms, excretion is carried out by the kidney which has different functions. Loop of Henle is the part of the kidney which helps in the reabsorption of water from the contents of renal tubules.

Complete answer:
(A) Desert mouse: Desert mouse is also known as a brown mouse which is a species of rodent. They have adapted to the lack of water and different foods in arid regions. They spend their day in underground burrows to avoid heat and feed at night. They produce concentrated urine to survive in an arid region. The loop of Henle from the contents of the renal tubule helps in the reabsorption of water and as a result, produces concentrated urine.
(B) Carnivorous bird: Carnivorous birds also have a kidney for reabsorption of water to avoid water loss. They don't have separate openings to excrete urine and feces. So, uric acid from the kidneys combined with waste products into the large intestine and released out through an opening called the cloaca.
(C) Freshwater fish: Freshwater fishes drink very little water and take in little water with their food. They don't have any kidneys. So, there is no loop of Henle for reabsorption. They excrete their waste through gills or skin.
(D) Garden bladder: It is a safe and very effective fertilizer used in the garden. It is an indirect method of providing the plants with urea. It boasts the nitrogen-phosphorus-potassium ratio in plants.

So, option (C) is the correct answer.

Note: In the above, we detailed the excretion of different animals. We get to know that different organisms have different organs for excretion which helps the body to eliminate all the toxic substances from our body.