CBSE Class 11 Biology Excretory Products and Their Elimination Worksheet Set A

Question. Toxic substances are detoxified in human body in
(a) kidney
(b) lungs
(c) liver
(d) stomach
Answer. C

Question. If Henle’s loop were absent from mammalian nephron which of the following is to be expected
(a) there will be no urine formation
(b) there will be hardly any change in the quality and quantity of urine formed
(c) the urine will be more concentrated
(d) the urine will be more dilute.
Answer. D

Question. Which blood vessel in mammals would normally carry the largest amount of urea?
(a) Dorsal aorta
(b) Hepatic vein
(c) Hepatic portal vein
(d) Renal vein
Answer. B

Question. Podocytes occur in 
(a) large intestine
(b) glomerulus of kidney
(c) wall of capillaries
(d) neck region
Answer. B

Question.. In ornithine cycle, enzyme arginase breaks down arginine into 
(a) Citrulline and ammonia
(b) Ornithine and ammonia
(c) Ornithine and urea
(d) Citrulline and urea.
Answer. C

Question. In which of the following minimum content of urea is present ? 
(a) Hepatic portal vein
(b) Portal vein
(c) Renal vein
(d) Vena cava
Answer. C

Question. The end product of ornithine cycle is 
(a) urea
(b) uric acid
(b) NH₃
(d) CO₂
Answer. A

ASSERTION REASON QUESTIONS

Directions : These questions consist of two statements, each printed as Assertion and Reason. While answering these questions, you are required to choose any one of the following five responses.
(a) If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
(b) If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
(c) If the Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(e) If the Assertion is incorrect but the Reason is correct.

Question. Assertion : During physiology of excretion, deamination does not take place in liver.
Reason : Deamination is a process to make use of excess of amino acids which cannot be incorporated into protoplasm.
Answer.D

Question. Assertion : Secreting hypotonic urine is effective in reducing urinary loss of water.
Reason : Hypotonic urine is more concentrated and higher in osmotic pressure than the blood.
Answer. D

Question. Assertion : Aldosterone is a steroid hormone and is important in the control of sodium and potassium ion concentration in mammals.
Reason : It upgrades sodium ion concentration in the ECF by promoting reabsorption of sodium ions from renal tubules and excretion of potassium ions in urine. 
Answer. A

Directions  : Each of these questions contains an Assertion followed by Reason. Read them carefully and answer the question on the basis of following options. You have to select the one that best describes the two statements.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.

Question. Assertion : Ultrafiltration takes place in presence of effective filtration pressure.
Reason : In ultrafiltration process, blood is filtered in Bowman’s capsule, filtered fluid contain protein & blood corpuscles also. 
Answer. C

Question. Assertion : In vertebrates, the liver is also referred as an accessory excretory organ.
Reason : Liver helps kidneys in the secretion of urine. 
Answer. C

Question. Assertion : Main constituent of human urine is ammonia.
Reason : If human urine is allowed to stand for some time, it smells strongly of ammonia. 
Answer. D

Question. Assertion : Hemodialysis can save and prolong the life of uremic patients.
Reason : Waste products like urea can be removed from the blood by the process of hemodialysis.
Answer. A

Question. Assertion : In the descending limb of loop of Henle, the urine is hypertonic, whereas in ascending limb of loop of Henle, the urine is hypotonic.
Reason : Descending limb is impermeable to sodium, while ascending limb is impermeable to water.
Answer. A