Title 19 Excretory products n their elimination - Topic wise complete Q n A.pdf ✅

© www.bankofbiology.com All rights reserved. 99 19. EXCRETORY PRODUCTS & THEIR 1. Note the relationship between first two words and fill up the fourth place. (Score 1) Ammonotelism: Ammonia Uricotelism: ...............  Answer: Uric acid 2. Note the relationship between first two words and fill up the fourth place. (Score 1) Birds: Uricotelism Mammals: ...............  Answer: Ureotelism 3. Imagine a terrestrial animal is Ammonotelic. Predict its consequences. (Score 2)  Answer If a terrestrial animal were Ammonotelic, it would need large amounts of water for ammonia excretion. It leads to dehydration and potential toxicity due to ammonia. 4. Complete the following sentences. (Score 2) a) Process of excretion of urea is called ............. b) In .........., NH3 is converted into less toxic urea.  Answer: a) Ureotelism b) Liver 5. Categorize the following animal groups under suitable titles. (Hint: types of excretion). (Score 3) Cartilaginous fishes, land snails, Aquatic insects, mammals, bony fishes, aquatic amphibians, terrestrial amphibians, Insects, reptiles, birds  Answer Ammonotelic Ureotelic Uricotelic Aquatic insects Bony fishes Aquatic amphibians Cartilaginous fishes Terrestrial amphibians Mammals Insects Land snails Reptiles Birds 6. (a) Define Uricotelism. (Score 2) (b) How does it help for water conservation of the body?  Answer: a) Uricotelism is the process of excretion of uric acid. b) Uric acid is water insoluble & less toxic. So, water is not needed for excretion. 7. Terrestrial animals are generally either ureotelic or uricotelic, not Ammonotelic. Why? (Score 2)  Answer Urea and uric acid are less toxic and require less water for excretion compared to ammonia. So they are suitable for water conservation in terrestrial environments. 8. Match the following: (Score 2) Excretory organs Found in a. Protonephridia (flame cells) 1. Crustaceans b. Nephridia 2. Insects c. Malpighian tubules 3. Flatworms, rotifers, some annelids & cephalochordate d. Antennal or green glands 4. Annelids  Answer Excretory organs Found in a. Protonephridia (flame cells) 3. Flatworms, rotifers, some annelids & cephalochordate b. Nephridia 4. Annelids c. Malpighian tubules 2. Insects d. Antennal or green glands 1. Crustaceans 9. In a class room discussion, your friend told that “Malpighian tubules are the kidneys of a cockroach.” How will you evaluate this statement? (Score 2)  Answer Considering the basic functions, I agree to this statement. Malpighian tubules in cockroaches serve to excrete metabolic waste and maintain osmotic balance, similar to the kidneys in higher organisms. HUMAN EXCRETORY SYSTEM 10. Complete the following sentences. (Score 2) a) Kidneys are reddish brown, bean-shaped structures situated between the levels of last thoracic and......... b) Kidney is enclosed in a tough, 3-layered fibrous ......... c) Hilum leads to funnel shaped cavity called ......... with projections called calyces. d) Each kidney has nearly one million tubular ..........  Answer: a) 3 rd lumbar vertebra b) Renal capsule c) Renal pelvis d) Nephrons 11. Name the following: (Score 2) a) Conical projections of renal medulla projecting into the calyces. b) Extensions of renal cortex between the medullary pyramids. c) The structural & functional units of kidney.
© www.bankofbiology.com All rights reserved. 100 d) An opening on the concave side of kidney through which blood vessels, nerves, lymphatic ducts and ureter enter the kidney.  Answer: a) Medullary pyramids (renal pyramids) b) Renal columns (Columns of Bertini) c) Nephron d) Hilum (hilus) 12. Given below is a diagram showing human urinary system. Label A to F. (Score 3)  Answer: A= Pelvis B= Renal medulla C= Renal artery D= Ureter E= Urinary bladder F= Urethra 13. The given diagram shows the longitudinal section of a kidney. Label A to F. (Score 3)  Answer: A= Medullary pyramid B= Renal calyx C= Renal vein D= Renal pelvis E= Renal capsule F= Renal column 14. Observe the diagram of a nephron. Label A to F. (Score 2)  Answer: A= Proximal convoluted tubule (PCT) B= Distal convoluted tubule (DCT) C= Descending limb of loop of Henle D= Ascending limb of loop of Henle E= Vasa recta F= Collecting duct 15. Identify the diagram and label A to E. (Score 3)  Answer: Malpighian body (renal corpuscle). A= Afferent arteriole B= Efferent arteriole C= Bowman’s capsule D= Glomerulus E= Proximal convoluted tubule (PCT) 16. Glomerulus and Bowman’s capsule together constitute ........... (Score 1)  Answer: Malpighian body (renal corpuscle) 17. State whether true or false. Also correct the false statements. (Score 3) a) Glomerulus is a tuft of capillaries formed by a fine branch of renal artery called efferent arteriole. b) Renal tubule begins with a double walled cup-like Bowman’s capsule, which encloses the glomerulus. c) The DCTs of many nephrons open into a collecting duct. d) Malpighian corpuscle, PCT and DCT are situated in renal medulla.  Answer: a) False. Glomerulus is a tuft of capillaries formed by a fine branch of renal artery called afferent arteriole. b) True. c) True. d) False. Malpighian corpuscle, PCT and DCT are situated in renal cortex. 18. Complete the sentence given below: The efferent arteriole forms a fine capillary network called ...... (a) ...... around the renal tubule. A minute vessel of this network runs parallel to Henle’s loop forming a ‘U’ shaped ...... (b) ...... (Score 2)  Answer: a) Peritubular capillaries b) Vasa recta 19. Each kidney has nearly one million nephrons. They are broadly classified into two. Briefly explain the two types of nephrons. (Score 2)
© www.bankofbiology.com All rights reserved. 101  Answer: 1. Cortical nephrons (85%): In this, the Henle’s loop is short and extends only very little into the medulla. Vasa recta is absent or highly reduced. 2. Juxtamedullary nephrons (15%): In this, Henle’s loop is long and runs deep into medulla. Vasa recta present. URINE FORMATION (PHYSIOLOGY OF KIDNEY) 20. Prepare a flowchart of filtrate flow in the nephron using the flow terms. (Score 2) Collecting duct, PCT, DCT, Ascending limb of Henle’s loop, descending limb of Henle’s loop, Bowman’s capsule  Answer: Bowman’s capsule → PCT → descending limb of Henle’s loop → Ascending limb of Henle’s loop → DCT Collecting duct. 21. a) Name the 3 processes of urine formation. (Score 2) b) What is the normal value of GFR?  Answer: a) Glomerular filtration, reabsorption & secretion. b) 125 ml/minute, i.e., 180 litres/day. 22. In nephrons, the glomerular capillary blood pressure causes filtration of blood through 3 layers. (Score 2) a) Name the three layers. b) Name the location of podocytes.  Answer: a) Endothelium of glomerular blood vessels. Epithelium of Bowman’s capsule. A basement membrane between these 2 layers. b) Bowman’s capsule. 23. The amount of glomerular filtrate formed per minute is called  Answer: Glomerular filtration rate (GFR). 24. a) Expand GFR. b) Even though GFR in a healthy person is 180 liters per day, the amount of urine released Per day is only about 1.5 litres. Give a reason. (Score 2)  Answer: a) Glomerular Filtration Rate. b) About 99% of the filtrate is reabsorbed by the renal tubules (Tubular reabsorption). 25. a) Write the significance of reabsorption in urine formation. b) Of the following substances which are reabsorbed by active transport? (Score 2) Glucose, Nitrogenous waste, Water, Amino acids  Answer: a) Conservation of water and useful substances. Concentration of urine. b) Glucose, Amino acids. 26. Match the following: (Score 3) Parts of nephron Function a. Glomerulus 1. Allows passage of small amounts of urea into medullary interstitium. b. Proximal convoluted tubule (PCT) 2. Filtration of blood. c. Descending limb of Loop of Henle 3. Conditional reabsorption of Na+ & water. d. Ascending limb of Loop of Henle 4. Permeable to water but almost impermeable to electrolytes. e. Distal convoluted tubule (DCT) 5. Impermeable to water but allows transport of electrolytes. f. Collecting duct 6. Reabsorbs most of the nutrients, and 70-80% of electrolytes & water.  Answer: Parts of nephron Function a. Glomerulus 2. Filtration of blood. b. Proximal convoluted tubule (PCT) 6. Reabsorbs most of the nutrients, and 70-80% of electrolytes & water. c. Descending limb of Loop of Henle 4. Permeable to water but almost impermeable to electrolytes. d. Ascending limb of Loop of Henle 5. Impermeable to water but allows transport of electrolytes. e. Distal convoluted tubule (DCT) 3. Conditional reabsorption of Na+ & water. f. Collecting duct 1. Allows passage of small amounts of urea into medullary interstitium. 27. a) What is the significance of tubular secretion? b) Name three regions of nephron where tubular secretion takes place. (Score 2)  Answer: a) It maintains ionic (Na-K balance) and acid-base balance (pH) of body fluids by selective secretion of H + , K+ & NH3 into the filtrate and absorption of HCO3 - from it. b) PCT, DCT, Collecting duct. 28. “Counter current system plays an important role in concentrating urine.” (Score 3)
© www.bankofbiology.com All rights reserved. 102 a) Name any two regions inside the kidney, where the counter current system is seen. b) What is meant by counter current mechanism? c) Name the two solutes responsible for the gradient of osmolarity from cortex (300 mOsmolL-1 ) to the inner medullary interstitium (1200 mOsmolL-1 ).  Answer: a) Henle’s loop & vasa recta. b) The flow of filtrate in the 2 limbs of Henle’s loop and the flow of blood through the 2 limbs of vasa recta are in opposite directions (counter current pattern). This is called Counter current mechanism. c) NaCl & urea. 29. State true or false. Also correct the false statements. a) About 125 ml of blood is filtered by the kidneys per minute. b) Small amount of urea enters the thin segment of the ascending limb of Henle’s loop which is transported back to the interstitium by the collecting tubule. c) DCT & collecting duct produce urine four times concentrated than the initial filtrate formed. d) An adult human excretes 2 to 2.5 litres of urine per day which contains 50-60 gm urea.  Answer: a) False. About 1100-1200 ml of blood is filtered by the kidneys per minute. b) True. c) True. d) False. An adult human excretes 1 to 1.5 litres of urine per day which contains 25-30 gm urea. 30. Events of micturition process are given below. Arrange them in correct sequence. i. Stretch receptors send impulses to CNS. ii. Contraction of smooth muscles of the bladder and relaxation of urethral sphincter. iii. Gradual filling of urinary bladder causes stretching. iv. The CNS passes on motor messages. v. Release of urine (micturition).  Answer: iii. Gradual filling of urinary bladder causes stretching. i. Stretch receptors send impulses to CNS. iv. The CNS passes on motor messages. ii. Contraction of smooth muscles of the bladder and simultaneous relaxation of the urethral sphincter. v. Release of urine (micturition). 31. The neural mechanism causing micturition is called  Answer: Micturition reflex 32. a) Give one word for the following: i. Presence of Glucose in Urine. ii. Presence of Ketone bodies in Urine. b) Which human disorder is having the above mentioned two symptoms? (Score 2)  Answer: a) i. Glycosuria. ii. Ketonuria b) Diabetes mellitus 33. Besides kidney, there are other organs which have some roles in excretion. Name any three such organs and mention their roles.  Answer: i. Lungs: Remove CO2 and water. ii. Liver: Secretes bile containing bilirubin, biliverdin, cholesterol, degraded steroid hormones, vitamins and drugs. iii. Skin: Sweat glands eliminate water, NaCl, some urea, lactic acid, etc. through sweat. Sebaceous glands eliminate sterols, hydrocarbons, waxes etc. through sebum. REGULATION OF THE KIDNEY FUNCTION 34. Observe the diagram: a. In which season ADH production is higher? b. Why the production of ADH varies in different seasons? (Score 2)  Answer: a) Summer season. b) Function of ADH is to stimulate the reabsorption of water from DCT. In summer season, water level of body is decreased. So ADH production is increased to reabsorb more water from DCT. In rainy season, water level of body will be high. So ADH production is decreased. 35. ............. is a sensitive region formed by cellular modification of DCT and the afferent arteriole at the location of their contact. (Score 1)  Answer: JGA (Juxta glomerular apparatus) 36. State whether the following statements are true/false. If false, correct it. (Score 3) a) ADH prevents diuresis. b) ANF causes the increase of blood pressure. c) Angiotensin-l activate adrenal cortex to release aldosterone.