Biology

Human Excretion and Kidney Physiology

1,152 Questions

Human excretion and kidney physiology questions test your understanding of the excretory system, including the role of renal tubules and glomerular filtration. You will also find topics on urine formation, body water absorption, and excretory products. This section is vital for medical and general science exam preparation.

Glomerular filtrationRenal tubule absorptionExcretory productsRole of sodium ionsHuman excretory system

Human Excretion and Kidney Physiology Questions

Multiple choice zoology control and coordination in living organisms regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Endocrine structure of kidney is 

  1. Cortex

  2. Medulla

  3. Juxtaglomerular apparatus

  4. Pelvis
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The juxtaglomerular apparatus is a type of endocrine organ that is small in size, located within kidneys and helps in the regulating the function of nephrons. This is mainly  involved in the secretion of renin and erythropoietin in response to changes in the renal blood pressure or blood flow. 

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Vasopressin is related with the concentration of urine.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Vasopressin causes resorption of water and electrolytes by the distal tubules and thereby reduces the loss of water through urine (diuresis) making urine concentrated. Hence, it is also called anti-diuretic hormone (ADH).
So, the correct option is 'True'.
Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Which one of the following statements is correct with respect to kidney function regulation ?

  1. When someone drinks lot of water, ADH release is suppressed

  2. Exposure to cold temperature stimulates ADH release

  3. An increase in glomerular blood flow stimulates formation of angiotensin II

  4. During summer when body loses lot of water by evaporation the release of ADH is suppressed
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When someone drinks lot of water which is excess amount for his body, as a result osmolarity of the blood will decreases.The decrease in osmolarity will suppress the release of ADH. Correct option is (A).

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Reabsorption of water in the nephron is controlled by ADH and aldosterone hormone.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
ADH facilitates water reabsorption from latter parts of the tubule, thereby preventing diuresis. Aldosterone causes reabsorption of Na+ and water from the distal parts of the tubule. Hence, both ADH and aldosterone control reabsorption of water in the nephron.
So, the correct option is 'True'.
Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Hormone which adsorbs water from renal tubule

  1. Insulin

  2. Glucangon

  3. ADH

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Vasopressin, also known as antidiuretic Hormone (ADH) is a hormone synthesized in the hypothalamus and stored in the posterior pituitary glands. It absorbs water from renal tubule thereby conserving water in our body. It constantly regulates and balances the water level of the body. Osmotic sensors and baroreceptors join with ADH in water metabolism.

Insulin helps to control blood glucose level whereas glucagon works to increase the sugar level in the bloodstream. 
So, the correct answer is 'ADH'.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

ADH helps in water elimination, making the urine hypotonic.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
ADH or antidiuretic hormone is produced in the hypothalamus and secreted from the neurohypophysis (posterior pituitary gland). ADH increases the reabsorption of water from the urine in the renal system back into the blood. Thus ADH conserves water in the kidneys and returns that fluid back to the general circulation. 
So the correct answer is 'False'.
Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Even in presence of hormone ADH, maximum water is reabsorbed in?

  1. Proximal convoluted tubule

  2. Distal convoluted tubule

  3. Both DCT and collecting tubule

  4. Loop pf Henle
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Over 180 liters of urine is produced in the human body every day. Out of this, only 1.5 liters is actually excreted. This means that 99% of the urine produced is reabsorbed in the body. Various solutes are absorbed in different parts of the renal tubule. Maximum water absorption takes place in the proximal convoluted tubule. 

So, the correct answer is 'Proximal convoluted tubule'.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Which of the following is involved in reabsorption of water in kidney?

  1. ADH

  2. PRL

  3. LH

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Antidiuretic hormone or ADH ( also known as vasopressin ) is involved in reabsorption of water in kidney. Antidiuretic hormone binds to receptors on cells in the collecting ducts of the kidney and promotes reabsorption of water back into the circulation. In the absense of antidiuretic hormone, the collecting ducts are virtually impermiable to water, and it flows out as urine.

Antidiuretic hormone stimulates water reabsorbtion by stimulating insertion of "water channels" or aquaporins into the membranes of kidney tubules. These channels transport solute-free water through tubular cells and back into blood, leading to a decrease in plasma osmolarity and an increase osmolarity of urine.
So, the correct option is 'ADH'.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Which of the following is a powerful vasconstrictor that increases the glomerular blood pressure and there the GFR?

  1. Renin

  2. Angiotensin-II

  3. Aidosterone

  4. ANF
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Osmoreceptors in the body are activated by changes in blood volume, body fluid volume and ionic concentration. A fall in glomerular blood flow/glomerular blood pressure/GFR can activate the JG cells to release renin which converts angiotensinogen in blood to angiotensin I and further to angiotensin II. Angiotensin II, being a powerful vasoconstrictor, increases the glomerular blood pressure and thereby GFR. Angiotensin II also activates the adrenal cortex to release aldosterone. Aldosterone causes reabsorption of Na$^+$ and water from the distal parts of the tubule. This also leads to an increase in blood pressure and GFR. This complex mechanism is generally known as the Renin-Angiotensin mechanism.
So, the correct option is 'Angiotensin-II'.
Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Osmoregulation is carried out by

  1. Ureter

  2. Nephron

  3. ACTH

  4. ADH
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The maintenance of constant osmotic pressure in the fluids of an organism by the control of water and salt concentrations. is called Osmoregulation. It  is carried out by 'anti-diuretic hormone'. 

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Vasopressin is responsible for :-

  1. Making urine dilute

  2. Dialating the blood vessel

  3. Decreasing filtrate concentration in PCT

  4. Increasing blood pressure
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Vassopressin or anti-diuretic hormone helps prevent loss of water from the body by increasing the reabsorption of water from the kidney and making urine more concentrated. It is also responsible for increasing the blood pressure by constricting the blood vessels. So, the correct option is 'increasing blood pressure'.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

Acidification of urine occurs in

  1. Proximal tubule

  2. Distal tubule

  3. Loop of henle

  4. None
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The proximal convoluted tubule is the primary site for the reabsorption of bicarbonate and the secretion of hydrogen ions, which contributes to the acidification of urine.

Multiple choice zoology excretion and osmoregulation regulation of urine formation properties of urine and regulation of urine formation coordination in human beings- chemical control

The opening of urinary bladder is called?

  1. Uriniferous tubule

  2. Nephron

  3. Urethra

  4. Ureter
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The urinary bladder stores urine collected from the ureters and expels it to the exterior through the urethra, which represents the terminal opening and passage of the urinary tract.