This chapter explains how the body removes metabolic wastes to maintain internal balance. It covers the structure and function of the kidney and nephron, processes like filtration, reabsorption, and secretion, and the role of hormones such as ADH and aldosterone in regulating urine formation. Understanding the excretory system is essential for grasping how organisms maintain homeostasis and eliminate harmful substances.
NEET MCQs Excretory Product and their Elimination
- Which of the following is correct with reference to haemodialysis?
a) Absorbs and resends excess of ions
b) The dialysis unit has a coiled cellophane tube
c) Blood is pumped back through a suitable artery after haemodialysis
d) Anti-heparin is added prior to haemodialysis - Polyuria is a condition in which
a) Amount of urine pass out is more b) Amount of urine pass out is less
c) No urine pass out d) No urine formation - Glucose, Na, and amino acid are actively transported substances, because
a) Their movement occurs according to concentration gradient
b) Their movement occurs against concentration gradient
c) ATP is not needed for transportation
d) They are transported by simple diffusion - Which of the following is both osmoregulator as well as nitrogenous product?
a) NH3 b) Urea c) Uric acid d) All of these - With respect to mode of excretion bony fishes are?
a) Osmoconformers b) Ammonotelic c) Uricotelic d) Uriotelic - Identify the true statements and choose the correct option accordingly
I. Blood vessel leading to the glomerulus is called efferent arteriole
II. Vasa-recta, peritubular capillaries and glomerulus, all have blood
III. Cortical nephrons have highly reduced vasa-recta
IV. Vasa-recta runs parallel to the Henle’s loop in the juaxta-medullary nephron
a) I, II and III b) I, II and IV c) I, III and IV d) II, III and IV - The yellow colour of urine is due to the presence of
a) Urea b) Uric acid c) Urochrome d) Bilirubin - Choose the correct option for A, B, C from given option a) A-Adrenal cortex, B-ADH, C-PCT b) A-Adrenal medulla, B-ADH, C-PCT
c) A-Hypothalamus, B-ADH, C-Distal tubules d) A-Lungs, B-ADH, C-Distal tubules - Structural and functional unit of the kidney is
a) Medulla b) Nephridia c) Nephron d) Hilum
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- Marine teleost fishes excrete
a) Uric acid b) Ammonia c) Urea d) None of these - Identify A to D in the given structure and choose the correct option accordingly a) A-Calyx, B-Cortex, C-Renal column, D-Ureter
b) A-Calyx, B-Cortex, C-Renal column, D-Urethra
c) A-Urethra, B-Cortex, C-Renal column, D-Calyx
d) A-Urethra, B-Calyx, C-Renal column, D-Cortex - The net filtration pressure in the glomerulus of the kidney is
a) 70 mm Hg b) 35 mm Hg c) 25 mm Hg d) 10 mm Hg - Loop of Henle is meant for the absorption of
a) Potassium b) Glucose c) Water d) Carbon dioxide - Functioning of kidney is efficiently regulated by
a) ANF b) JGA c) Both (a) and (b) d) Lungs - Select the correct pathway for the passage of urine in humans
a) Renal vein → Renal ureter → Bladder → Urethra
b) Collecting tubule → Ureter → bladder → Urethra
c) Pelvis → Medulla → Bladder → Urethra
d) Cortex → Medulla → Bladder → Ureter - The waste products produced in man which need excretion are?
a) Carbon dioxide b) Urea and salts c) Excess of water d) All of these - Excretion of nitrogenous waste product in semisolid from occurs in
a) Ureotelic animals b) Ammonotelic animals
c) Uricotelic animals d) Amniotes - Juxta glomerular apparatus is modification in the
a) Afferent atriole and PCT b) Afferent atriole and DCT
c) Efferent atriole and DCT d) Efferent atriole and PCT - A large quantity of fluid is filtered every day by the nephrons in the kidneys. Only about 1% of it is
excreted as urine. The remaining 99% of the filtrate
a) Gets collected in the renal pelvis b) Is lost as sweat
c) Is stored in the urinary bladder d) Is reabsorbed into the blood - Autoregulation of GFR (Glomerulus Filtration Rate) is takes place by
a) Renin angiotensis mechanism b) Juxtaglomerulus apparatus
c) Vasopressin d) All of the above - Physiologically urea is produced by the action of an enzyme
a) Arginase b) Urease c) Uricase d) None of these - Malpighian body or renal corpuscle is/are
a) Bowman’s capsule b) Glomerulus
c) Both (a) and (b) d) Proximal convoluted tubule - Among ammonia, uric acid and urea, which one is the most soluble?
a) Ammonia b) Uric acid c) Both (a) and (b) d) Urea - The living steady state has a self-regulatory mechanism which is known as
a) Feed back mechanism b) Homeotherms
c) Homozygous d) Homeostasis
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- Uricotelism is found in
a) Mammals and birds b) Fishes and freshwater protozoans
c) Birds, reptiles and insects d) Frogs and toads - Volume of urine is regulated by
a) Aldosterone b) Aldosterone and testosterone
c) ADH d) Aldosterone and ADH - Urine is yellow in colour, due to
a) Prochrome b) Haemoglobin c) Urochrome d) Creative - Vasa recta is minute vessel of Peritubular capillaries network, which is
a) Also known as juxta-glomerular apparatus b) Running parallel to loop of Henle
c) Running parallel to PCT d) Running parallel to DCT - A person is undergoing prolonged fasting. His urine will be found to contain abnormal quantities of
a) Fats b) Ketones c) Amino acids d) Glucose - If excess water passes out from tissues without being restored by kidneys, the cells would
a) Burst open and die b) Not be affected at all
c) Extract water from plasma d) Shrivel and die - Part of the kidney through which the ureter, blood vessels and nerves enters into it is
a) Renal cortex b) Renal medulla c) Hilum d) Urethra - Which one of the following correctly explains the function of a specific part of a human nephron?
a) Henle’s loop – Most reabsorption of the major
substances from the glomerular filtrate b) Distal convoluted tubule−Reasorption of ions into
the surrounding blood capillaries
c) Afferent arteriole−Carries the blood away from
the glomerulus towards renal vein d)
Podocytes−Creat minute spaces (slit pores) for
the filteration of blood into the Bowman’s
capsule
- When does glomerular filtration occurs in Bowman’s capsule?
a) When hydrostatic pressure of blood in the glomerulus is 70 mm Hg and net filtrate pressure is -25 mm
Hg
b) When hydrostatic pressure of blood in the glomerulus is 70 mm Hg and net filtrate pressure is -35 mm
Hg
c) When hydrostatic pressure of blood in the glomerulus is 70 mm Hg and net filtrate pressure is 10 mm
Hg
d) When hydrostatic pressure of blood in the glomerulus is 70 mm Hg and net filtrate pressure is -70 mm
Hg - Smell of urine is due to the
a) Urochrome b) Urinode c) Urea d) Melanin - The counter current mechanism operates in nephron
a) In ascending and descending limb of vasa recta b) In ascending limb of Henle’s loop
c) In descending limb of Henle’s loop d) Between the loop of Henle and vasa recta - The average quality of urea excreted in urine by man per day is
a) 1-5 g b) 25-30 g c) 1-1.5 L d) 80 g - Melanuria is caused by the abnormal catabolism of
a) Alanine b) Tyrosine c) Proline d) Tryptophan - Which one of the following statements is correct with respect to kidney function regulation?
a) Exposure to cold temperature stimulates ADH release
b) An increase in glomerular blood flow stimulates formation of angiotensin II
c) During summer when body loses lot of water by evaporation, the release of ADH is suppressed
d) When someone drinks lot of water ADH release is stopped - Blood leaving liver and going towards heart is rich in
a) Bile b) Urea c) Ammonia d) Oxygen - Urea synthesis occurs in
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a) Kidney b) Liver c) Brain d) Muscles
- Green glands present in some arthropods help in
a) Respiration b) Excretion c) Digestion d) Reproduction - I. Na+ II. H2O
III. HCO3 − IV. H+
V. K+ VI. NH3
Which of the given ions are reabsorbed and secreted DCT?
Reabsorb Secreted
a) I, II and III IV, V and VI b) IV, V and VI I, II and III
c) I, II and V III, IV and V d) III, IV, and VI I, II and V - Reabsorption of the filtrate in the renal tubules takes place by
a) Active means b) Passively means c) Either (a) or (b) d) Osmosis means - Aldosterone causes reabsorption of …A… from distal part of tubule. This leads to increase in …B…
Here A and B refers to
a) A-Na+; B – GFR b) A-water; B-GFR c) Both (a) and (b) d) A-Cl−; B-GFR - In human, excretory system consists of
I. pair of kidneys II. one pair of ureters
III. urinary bladder III. Urethra
V. skin VI. Lungs
VII. liver
a) I, II, III and II b) I, II, III and IV
c) I, II, III and IV d) I, II, III, IV, V, IV and VII - The net pressure gradient that cause the fluid to filter out of the glomeruli in the capsule is
a) 20 mm Hg b) 75 mm Hg c) 30 mm Hg d) 50 mm Hg - In the glomerulus of the nephron, the afferent arteriole is
a) Narrower than efferent arteriole b) Wider than efferent arteriole
c) Of some diameter as efferent arteriole d) Of same diameter as vasa-recta - NaCl is returned to interstitium by
a) Ascending limb of Henle’s loop b) Descending limb of Henle’s loop
c) Ascending limb of vasa recta d) Descending limb of vasa recta - Identify A to D in the following structure and choose the correct option for A, B, C and D a) A-Afferent arteriole, B-Efferent arteriole, C-Bowman’s capsule, D-Proximal convoluted tubule
b) A-Efferent arteriole, B-Afferent arteriole, C-Bowman’s DTC
c) A-Efferent arteriole, B-Efferent arteriole, C-Bowman’s capsule, D-DCT
d) A-Efferent arteriole, B-Afferent arteriole, C-Bowman’s capsule, D-DCT - Choose the correct statements
a) Sebaceous gland eliminate sterols, hydrocarbons, waxes
b) Secretion of sebaceous gland provide oily protective covering of skin
c) Small amount of nitrogenous wastes eliminated through saliva
d) All of the above - Choose the correct option with respect to the maximum urea level
a) Renal vein b) Hepatic vein c) Pulmonary artery d) Pulmonary vein - Renin is secreted from
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a) Juxtaglomerular cells b) Podocytes c) Nephridia d) Stomach
- Main function of DCT of nephron is to maintain the
a) pH in blood b) Na-K balance of blood
c) Both (a) and (b) d) Temperature of blood - Uric acid is the chief nitrogenous excretory component of
a) Man b) Earthworm c) Cockroach d) Frog - A fall in the GFR rate activates the
a) JG cells to release renin b) JG cells to release aldosterone
c) JG cells to release epinephrine d) JG cells to release nor-epinephrine - Name the condition when the concentration of ketone body increases in urine
a) Acromegaly b) Ketonuria c) Diabetes insipidus d) Cushing’s disease - The excretory organ in crustaceans, like prawns is
a) Antennal glands b) Nephridia c) Flame cells d) Malpighian tubules - Which one of the following statements in regard to the excretion by the human kidneys is correct?
a) Descending limb of loop of Henle is impermeable to water
b) Distal convoluted tubule is incapable of reabsorption HCO3
c) Nearly 99 per cent of the glomerular filtrate is reabsorbed by the renal tubules
d) Ascending limb of loop of Henle is impermeable to electrolytes - Glucose and amino acids are reabsorbed in the
a) Proximal tubule b) Distal tubule c) Collecting duct d) Loop of Henle - What is the obligatory water reabsorption?
a) Reabsorption of water from PCT b) Reabsorption of water from loop of Henle
c) Both (a) and (b) d) Water secretion by Bowman’s capsule - Ammonia or urea are the waste products, which are derived from
a) Proteins b) Carbohydrate c) Lipids d) Fats - Transport of electrolytes through loop of Henle takes place by
a) Actively b) Passively c) Both (a) and (b) d) Diffusion - Choose the correct statement.
a) The juxta medullarly nephrons have reduced Henle’s loop
b) Vasa recta is well developed in cortical nephrons
c) The PCT and DCT are situated in the medulla of the kidney
d) The ascending limb of the Henle’s loop extends as the DCT - Which one is mismatched?
a) Bowman’s capsule−Glomercular filtration b) PCT−Absorption of Na+ and K+
c) DCT−Absorption of glucose d) None of the above - In which of the following regions of a nephron, does maximum reabsorption of useful substances takes
place?
a) Henle’s loop b) Glomerulus
c) Proximal convoluted tubule d) Distal convoluted tubule - Urea cycle is also called
a) Kreb’s cycle b) Henselet cycle c) Kreb-Henselet cycle d) Dark reaction - Percentage of electrolytes and water reabsorbed by PCT is
a) 60-70 b) 70-80 c) 80-90 d) 90-95 - ADH is also called
a) Vasopressin b) Prolactin c) Urease d) Oxytocin - Gout is a condition in which
a) High level of urine in blood is found b) High level of urea in blood is found
c) High level of uric acid in blood is found d) All of the above - During urine formation, which of the following processes create high osmotic pressure in the uriniferous
tubule?
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a) Active Na+ absorption, followed by absorption of Cl−
b) Active Cl− absorption, followed by absorption of Na+
c) Active secretion of Na+ into efferent arteriole followed by absorption of Cl− into efferent renal arteriole
d) Active secretion of Cl− and absorption of Na+ into efferent renal arteriole
- Order of toxicity among ammonia, urea and uric acid (from lower to higher) is
a) Uric acid < urea < ammonia b) Uric acid < ammonia< urea
c) Urea < uric acid < ammonia d) Ammonia < urea < uric acid - Which substance is in higher concentration in blood than in glomerular filtrate?
a) Water b) Glucose c) Urea d) Plasma proteins - Average pH of human urine is
a) 6.0 b) 9.0 c) 3.0 d) 7.0 - A portion of uric acid is converted to urea and ammonia by intestinal
a) Urogenolysis b) Ureolysis c) Uricolysis d) Ureotolysis - Mammals have the ability to produce
a) Isotonic urine b) Hypertonic urine c) Hypotonic urine d) Acidic urine - The process of excretion is the
a) Removal of useful substances from the body
b) Removal of metabolic waste from the body
c) Removal of the substances which have never been a part of the body
d) Formation of useful substances in the body - Which one of the following amino acids is not found in proteins?
a) Arginine b) Ornithine c) Aspartic acid d) Tyrosine - Inner to the hilum of the kidney, there is a broad funnel-shaped space called
a) Renal pelvis b) Medulla c) Cortex d) Adrenal gland - Vasopressin released from the neurohypophysis is mainly responsible for
a) Facultative reabsorption of water through Henle’s loop
b) Obligatory reabsorption of water through Bowman’s capsule
c) Facultative reabsorption of water through DCT
d) Obligatory reabsorption of water through PCT - What will happen if the stretch receptors of the urinary bladder wall are totally removed?
a) Urine will not collect in the bladder
b) Micturition will continue
c) Urine will continue to collect normally in the bladder
d) There will be no micturition - Glomerulus is a tuft of capillaries formed by …A… (A fine branch of renal artery). Blood from the
glomerulus is carried away by an …B…
Select the correct option for A and B to complete the given NCERT statement
a) A-efferent atriole; B-afferent atriole b) A-efferent atriole; B-efferent atriole
c) A-afferent atriole; B-afferent atriole d) A-afferent atriole, B-efferent atriole - RAAS
a) Is triggered when juxta-glomerular cells of JGA releases renin in response to various stimuli
b) Is responsible for regulation of kidney function
c) Is a powerful mechanism responsible for regulation of functioning of heart
d) Both (a) and (b) - Nephritis is caused by
a) Fungi b) Bacteria c) Virus d) Protozoa - Ammonia is converted into urea in
a) Kidney b) Lungs c) Liver d) Spleen - Solenocytes are used for
a) Elimination of nitrogenous excretory wastes b) Respiration
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c) Digestion d) All of the above
- Nitrogenous waste products are eliminated mainly as
a) Urea in tadpole and uric acid in adult frog b) Urea in adult frog and ammonia in tadpole
c) Urea in tadpole as well as in adult frog d) Urea in tadpole and ammonia in adult frog - Acceossory excretory organs are
I. skin II. lungs
III. liver IV. sebaceous gland
Choose the correct option
a) I and II b) II and III c) III and IV d) I, II, III and IV - Erythropoietin is secreted from
a) Pituitary gland b) Pancreas c) Adrenal gland d) Kidney - A fall in GFR activate …A… to release …B…, which converts angiotensinogen in blood to …C… and further to
…D…
Choose the correct option for A, B, C, D from given options
a) A-JG cells, B-renin, C-angiotensin-I, D-angiotensin-II
b) A-renin, B-JG cells, C-angiotensin-I, D-angiotensin-II
c) A-renin, B-JG cells, C-angiotensin-II, D-angiotensin-I
d) A-JG cells, B-angiotensin, A-renin-I, D-angiotensin-II - The human kidney
a) Is responsible for the storage of nutrients such as glycogen
b) Concentrates the urine by actively transporting water out of the filtrate
c) Produces more dilute urine when the collection ducts become less permeable to water
d) Responds to antidiuretic hormone by increasing urine output - The excretory material of bony fish is
a) Urea b) Protein c) Ammonia d) Amino acid - The urine is
a) Hypotonic to blood and isotonic in medullarly fluid
b) Hypertonic to blood and isotonic to medullarly fluid
c) Isotonic to blood and hypotonic to medullarly fluid
d) Isotonic to blood and hypertonic to medullarly fluid - I. ADH
II. Renin-angiotensin
III. ANF
IV. Counter – current mechanism which
Choose the option containing factors, which regulates the osmoregulation of body fluids?
a) I, II and III b) II, III and IV c) I, II and IV d) All of the above - Counter current mechanism helps to maintain a concentration gradient. This gradient help in
a) Easy passage of water from medulla to collecting tubule and thereby concentrating urine
b) Easy passage of water from collecting tubule to interstitial fluid and thereby concentrating urine
c) Easy passage of water from medullary interstitial fluid to collecting tubule and thereby diluting urine
d) Inhibition of passage of water between the collecting tubule and medulla and so isotonic urine is
formed - Choose the correct statement
I. Renal artery transport blood to kidney
II. Loop of Henle concentrate urine
III. Podocytes occur in inner wall of Bowman’s capsule
IV. Ultrafiltrate is blood plasma minus protein
a) I, II and III b) I, II and IV c) I, II and IV d) None of these - While urine formation progress, which of the following process takes place in the region labelled as A, B, C
and D in the given diagram?
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a) A-Collection of urine, B-Secretion C-Reabsorption, D-Pressure filtration
b) A-Pressure filtration, B-Reabsorption C-Secretion, D-Collection of urine
c) A-Pressure filtration, B-Secretion C-Reabsorption, D-Collection of urine
d) A-Reabsorption, B-Secretion C-Pressure filtration, D-Collection of urine
- Which one is the component of ornithine cycle?
a) Ornithine, citrulline and fumaric acid b) Ornithine, citrulline and arginine
c) Ornithine, citrulline and alanine d) Amino acids are not used - Collecting duct of nephron extends kidney from cortex to
a) Capsule region b) Inner part of medulla
c) Outer part of medulla d) Middle part of medulla - Kidney stones are produced due to deposition of uric acid and
a) Silicates b) Minerals c) Calcium carbonate d) Calcium oxalate - Anuria is failure of
a) Kidney to form urine b) Tubular secretion in kidney
c) Tubular filtration in kidney d) Tubular reabsorption in kidney - Choose the correct order of urine formation in human
a) PCT → ALH → DLH → DCT → CD b) ACH → DLH → PCT → DCT → CD
c) PCT → DLH → ALH → DCT → CD d) CD → DCT → ACH → DLH → PCT - Consider the following statements
I. Flame cells are excretory structures in flatworms.
II. Green glands are excretory organs in annelids.
III.Columns of Bertini are the conical projections of renal pelvis into renal medulla between the renal
pyramids.
a) I and II correct b) II and III incorrect c) I and III correct d) I, II and III correct - Arrange the following parts of the nephron in a sequential manner and select the correct option
accordingly
I. Glomerulus
II. Bowman’s capsule
III. Henle’s loop
IV. Proximal convoluted tubule
V. Collecting duct
VI. Distal convoluted tubule
a) I→II→III→IV→V→VI b) I→II→IV→III→VI→V c) I→II→IV→III→V→VI d) VI→III→II→I→VI→V - The outline of principal event of urination is given below in unorder manner
I. Stretch receptors on the wall of urinary bladder send signal to the CNS
II. The bladder fills with urine and becomes distended
III. Micturition
IV. CNS passes on motor messenger to initiate the contraction smooth muscles of bladder and
simultaneous relaxation of urethral sphincter
The correct order of steps for urination is
a) II→I→IV→III b) IV→III→II→I c) II→I→III→IV d) III→II→I→IV - Malpighian tubules are the excretory structures of
a) Insects b) Mammals c) Birds d) Reptiles
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