Excretory System (Human Anatomy and Physiology)

Total Questions: 18

11. The average blood flow through kidneys per minute is [56th to 59th B.P.S.C. (Pre) 2015]

Correct Answer: (b) 1200 cc
Solution:Kidneys are the most important organ in our body. Kidneys help in purification of blood and also removes toxic materials from our body through urine. Our kidneys purify around 1500 litre of blood and excrete approximately 1.5 litre urine per day. About 1200 ml (cc) of blood flows through both the kidneys per minute and out of it about 1 ml of urine is formed per minute.

12. When kidneys fail to function, there is accumulation of– [Uttarakhand P.C.S. (Pre) 2007]

Correct Answer: (d) Nitrogenous waste products in the blood
Solution:Metabolism refers to all of the body’s chemical processes, the digestion of food and the elimination of waste. The main nitrogenous wastes are ammonia, urea and uric acid. Urea is formed from gluconeogenesis of amino acids. Urea is one of the primary components of urine. When kidneys fail to function, there is accumulation of nitrogenous waste products in the blood.

13. Which of the following is not the normal function of the human kidney? [U.P.P.C.S. (Pre) 2011]

Correct Answer: (b) Regulation of sugar level in the blood
Solution:The main function of the pancreas is to produce insulin hormones. The pancreas plays an important role in digestion and in regulating blood sugar level in the blood, while other three options are the normal functions of human kidneys.

14. The major chemical compound found in human kidney stones is – [I.A.S. (Pre) 1998]

Correct Answer: (c) Calcium oxalate
Solution:Calcium oxalate is a chemical compound that forms envelope-shaped crystals, known in plants as raphides. A major constituent of human kidney stones is calcium oxalate.

Raphides are needle-shaped crystals of calcium oxalate that can be found in many plant cells. They can act as a defense mechanism against herbivores. Calcium oxalate is a major component of kidney stones, often forming on a base of calcium phosphate. Approximately 75% of all kidney stones are composed primarily of calcium oxalate. Calcium oxalate also forms a scale called beerstone on the interior of containers used in brewing.

15. Kidney stones are formed due to : [U.P. R.O./A.R.O. (Pre) 2023]

Correct Answer: (b) Crystallization of Oxalates
Solution:A kidney stone is a hard object that is made from chemicals in the urine. There are four types of kidney stones : calcium oxalate, uric acid, struvite, and cystine. The most common type of kidney stone which is created when calcium combines with oxalate in the urine. Oxalate is one type of substance that can form crystals in the urine. This can happen if there is too much oxalate, too little liquid, and the oxalate 'sticks' to calcium while urine is being made by the kidneys.

16. The 'stones' formed in human kidney consist mostly of : [I.A.S. (Pre) 2000]

Correct Answer: (a) Calcium oxalate
Solution:A kidney stone is a hard object that is made from chemicals in the urine. There are four types of kidney stones : calcium oxalate, uric acid, struvite, and cystine. The most common type of kidney stone which is created when calcium combines with oxalate in the urine. Oxalate is one type of substance that can form crystals in the urine. This can happen if there is too much oxalate, too little liquid, and the oxalate 'sticks' to calcium while urine is being made by the kidneys.

17. What amongst the following is responsible for the formation of stone in the human kidney? [U.P.P.C.S. (Pre) (Re. Exam) 2015]

Correct Answer: (b) Calcium oxalate
Solution:A kidney stone is a hard object that is made from chemicals in the urine. There are four types of kidney stones : calcium oxalate, uric acid, struvite, and cystine. The most common type of kidney stone which is created when calcium combines with oxalate in the urine. Oxalate is one type of substance that can form crystals in the urine. This can happen if there is too much oxalate, too little liquid, and the oxalate 'sticks' to calcium while urine is being made by the kidneys.

18. The element excreted through human sweat is : [63rd B.P.S.C. (Pre) 2017]

Correct Answer: (e) None of the above/More than one of the above
Solution:Sweat is produced by the skin in the form of liquid to regulate the body temperature. It is the part of the excretory function of the skin. Sodium, potassium, calcium, magnesium and many other trace elements (eg. zinc, copper, iron, chromium, nickel and lead) are excreted through human sweat.