Class 11 Biology (NCERT / JAC Board)

1. Which of the following nitrogenous wastes is the most toxic and requires large amounts of water for its elimination?

• A. Ammonia
• B. Urea
• C. Uric acid
• D. Creatinine

2. Reptiles, birds, land snails, and insects excrete nitrogenous wastes mainly as:

• A. Uric acid
• B. Urea
• C. Ammonia
• D. Amino acids

3. What are the excretory structures found in platyhelminthes (e.g., Planaria)?

• A. Flame cells (Protonephridia)
• B. Nephridia
• C. Malpighian tubules
• D. Antennal glands

4. Antennal glands or green glands perform the excretory function in:

• A. Crustaceans (e.g., Prawns)
• B. Insects (e.g., Cockroach)
• C. Annelids (e.g., Earthworm)
• D. Molluscs

5. On average, how much urea is excreted out by a human adult per day?

• A. 25–30 grams
• B. 5–10 grams
• C. 50–60 grams
• D. 100 grams

6. Functional unit of the human kidney is called:

• A. Nephron
• B. Neuron
• C. Glomerulus
• D. Henle's loop

7. A Malpighian body or renal corpuscle consists of:

• A. Glomerulus and Bowman's capsule
• B. Glomerulus and PCT
• C. Bowman's capsule and Loop of Henle
• D. DCT and Collecting duct

8. Epithelial cells of Bowman's capsule called podocytes leave intricate spaces called filtration slits in the:

• A. Visceral layer of Bowman's capsule
• B. Parietal layer of Bowman's capsule
• C. Endothelium of glomerular blood vessels
• D. Basement membrane

9. Normal Glomerular Filtration Rate (GFR) in a healthy individual is approximately:

• A. 125 mL/minute (180 Litres/day)
• B. 180 mL/minute
• C. 125 Litres/day
• D. 50 mL/minute

10. Juxtaglomerular Apparatus (JGA) releases which hormone in response to a fall in GFR?

• A. Renin
• B. Rennet
• C. Erythropoietin
• D. Aldosterone

11. Maximum reabsorption of water, electrolytes, and essential nutrients occurs in which part of the nephron?

• A. Proximal Convoluted Tubule (PCT)
• B. Distal Convoluted Tubule (DCT)
• C. Descending limb of Loop of Henle
• D. Collecting duct

12. The descending limb of Loop of Henle is:

• A. Permeable to water but almost impermeable to electrolytes
• B. Impermeable to water but permeable to electrolytes
• C. Impermeable to both water and electrolytes
• D. Permeable to electrolytes only

13. The ascending limb of Loop of Henle is:

• A. Impermeable to water but allows transport of electrolytes
• B. Permeable to water only
• C. Permeable to water and electrolytes equally
• D. Impermeable to both water and salts

14. Anti-Diuretic Hormone (ADH) or Vasopressin acts mainly on DCT and collecting duct to cause:

• A. Increased reabsorption of water, producing concentrated urine
• B. Decreased reabsorption of water, producing dilute urine
• C. Increased excretion of Na+ ions
• D. Inhibition of renin secretion

15. Atrial Natriuretic Factor (ANF) is secreted by heart atria when blood pressure increases, causing:

• A. Vasodilation and decrease in blood pressure
• B. Vasoconstriction and increase in blood pressure
• C. Secretion of renin and aldosterone
• D. Increased water reabsorption in PCT

16. The mechanism that maintains a high concentration gradient in the renal medullary interstitium is:

• A. Counter-current mechanism of Henle's loop and vasa recta
• B. Active transport in PCT
• C. Ultrafiltration in glomerulus
• D. Micturition reflex

17. The process of release of urine from the urinary bladder is called:

• A. Micturition
• B. Hemodialysis
• C. Ultrafiltration
• D. Exudation

18. Accumulation of urea in blood due to kidney failure is known as:

• A. Uremia
• B. Anuria
• C. Glycosuria
• D. Ketonuria

19. Presence of glucose (Glycosuria) and ketone bodies (Ketonuria) in urine is an indicator of:

• A. Diabetes mellitus
• B. Diabetes insipidus
• C. Bright's disease
• D. Glomerulonephritis

20. In insoluble mass of crystallized salts (e.g., oxalates) formed within the kidney is termed:

• A. Renal calculi (Kidney stone)
• B. Glomerulonephritis
• C. Uremia
• D. Cystitis

21. Inflammation of glomeruli of kidneys is called:

• A. Glomerulonephritis
• B. Renal calculi
• C. Uremia
• D. Gout

22. Human kidneys are located between the levels of:

• A. Last thoracic and third lumbar vertebra
• B. 1st thoracic and 5th lumbar vertebra
• C. 12th thoracic and 1st lumbar vertebra
• D. 5th thoracic and 12th thoracic vertebra

23. Cortical nephrons differ from juxtamedullary nephrons because cortical nephrons have:

• A. Short Loop of Henle extending only little into medulla
• B. Long Loop of Henle running deep into medulla
• C. Well developed vasa recta
• D. Absence of glomerulus

24. Blood vessel that enters the glomerulus is called:

• A. Afferent arteriole
• B. Efferent arteriole
• C. Renal vein
• D. Vasa recta

25. Which of the following is NOT normally filtered into Bowman's capsule during ultrafiltration?

• A. Plasma proteins
• B. Glucose
• C. Amino acids
• D. Urea

26. Aldosterone causes reabsorption of Na+ and water from which region of the nephron?

• A. Distal Convoluted Tubule (DCT)
• B. Proximal Convoluted Tubule (PCT)
• C. Descending Henle's loop
• D. Glomerulus

27. Which accessory organ aids in excretion by removing sterols, hydrocarbons, and waxes through sebum?

• A. Sebaceous glands
• B. Sweat glands
• C. Liver
• D. Lungs

28. Human urine is normally slightly acidic with an average pH of:

• A. 6.0
• B. 7.4
• C. 4.5
• D. 8.2

29. What percentage of blood pumped by each ventricle of heart is filtered by kidneys per minute?

• A. 20–25% (about 1100–1200 mL)
• B. 50%
• C. 5–10%
• D. 70%

30. During hemodialysis, which anticoagulant is added to blood drawn from the patient before pumping into the dialyzing unit?

• A. Heparin
• B. Anti-heparin
• C. Histamine
• D. Thrombin