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

ADH takes part in

  1. Water retention in urine
  2. $Na^+$ reabsorption

  3. Reducing urea formation

  4. Absorption of water from urine
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The reabsorption of water in the kidneys is under the control of ADH. It triggers the release of aldosterone which increases the concentration of sodium ions in the blood. The increased salt concentration in the blood increases the blood osmotic potential which further increases the reabsorption of water into the collecting tubule.
So, the correct answer is 'Absorption of water from 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

Which ones regulate solute reabsorption during urine formation?

  1. ADH and angiotensin

  2. Angiotensin II and angiotensin I

  3. Norepinephrine and epinephrine

  4. Angiotensin II and aldosterone
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

 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. Hence Angiotensin  II and aldosterone regulate solute reabsorption during urine formation.

So, the correct answer is 'Option D'.

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

Excretion of dilute urine is due to

  1. More secretion of aldosterone

  2. Less secretion of vasopressin

  3. Less secretion of glucagon

  4. More secretion of insulin
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Aldosterone is the hormone produced by the adrenal gland. Aldosterone balance sodium and potassium in our body. When Excess of aldosterone is produced by the adrenal gland causes the body to lose potassium and retain sodium. It leads to excretion of dilute urine.

So, the correct answer is 'More secretion of aldosterone'.

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

During summer season, which hormone concentration is maintained at high level?

  1. Insulin

  2. Vasopressin

  3. Oxytocin

  4. Corticoid
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

During the summer season, The hormone whose concentration is maintained at a high level is Vasopressin or ADH(antidiuretic hormone). When excess water is lost through urine the blood volume is decreased and its osmolarity is increased which stimulates the posterior pituitary to release ADH.ADH decreases the volume of urine by increasing the reabsorption of water by kidneys and prevents diuresis. Hence it is also called antidiuretic hormone.

So, the correct answer is 'Vasopressin'.

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

Identify the correct statement regarding urine formation.

  1. Counter-current mechanism works around glomerulus and PCT

  2. To prevent diuresis, ADH facilitates water reabsorption from the later parts of the tubule

  3. Maximum absorption of electrolytes occurs in Henles loop

  4. A decrease in blood pressure can increase glomerular filtration rate

  5. The collecting duct is impermeable to water and thus helps in diluting the urine
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The term diuresis refers to the excessive production of urine. When excess water is lost through urine the blood volume is decreased and its osmolarity is increased which stimulates the posterior pituitary to release ADH.ADH decreases the volume of urine by increasing the reabsorption in the later parts of the tubule and prevents diuresis. 

So, the correct answer is 'To prevent diuresis, ADH facilitates water reabsorption from the later parts of the 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

ADH takes part in

  1. Reabsorption of $Na^+$

  2. Reabsorption of watera

  3. Tabular secretion of creatinine

  4. Tubular secretion of urea
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When excess water is lost through urine the blood volume is decreased and its osmolarity is increased which stimulates the posterior pituitary to release ADH. ADH decreases the volume of urine by increasing the reabsorption of water by kidneys and prevents diuresis. Thus ADH takes part in reabsorption of water.

So, the correct answer is 'Option B'.

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 is correct

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

  2. During summer, when body loses a lot of water by evaporation, the release of ADH is suppressed

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

  4. Exposure to cold temperature stimulates ADH release
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When excess water is lost through urine the blood volume is decreased and its osmolarity is increased which stimulates the posterior pituitary to release ADH.ADH decreases the volume of urine by increasing the reabsorption by kidneys and prevents diuresis. Hence when someone drinks a lot of water, ADH release is suppressed.

So, the correct answer is 'When someone drinks a lot of water, ADH release is suppressed'

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 hormone helps to prevent the diuresis?

  1. FSH

  2. LH

  3. MSH

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

The term diuresis refers to the excessive production of urine. When excess water is lost through urine the blood volume is decreased and its osmolarity is increased which stimulates the posterior pituitary to release ADH.ADH decreases the volume of urine by increasing the reabsorption by kidneys and prevents diuresis. Hence it is also called antidiuretic hormone.

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

Concentration of urine is controlled by

  1. ACTH

  2. MSH

  3. ADH

  4. Oxytocin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The hormone ADH (vasopressin) is released from the neurohypophysis (posterior pituitary gland). ADH is synthesized by the hypothalamus and stored in the neurohypophysis. When blood volume is decreased or sodium concentration of blood is increased due to dehydration the ADH is released from the neurohypophysis. ADH causes retention of water by kidneys and maintains blood volume. Hence concentration of urine is controlled by ADH.
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

The hormone ADH is released from the 

  1. Adenohypophysis

  2. Neurohypophysis

  3. Adrenal gland

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The hormone ADH (vasopressin) is released from the neurohypophysis (posterior pituitary gland). ADH is synthesized by the hypothalamus and stored in the neurohypophysis. When blood volume is decreased or sodium concentration of blood is increased due to dehydration the ADH is released from the neurohypophysis. ADH causes retention of water by kidneys and maintains blood volume.

So, the correct answer is 'Neurohypophysis'.

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

Facultative absorption of water from primary urine is influenced by the hormone

  1. Androgens

  2. Epinephrine

  3. Vasopressin

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

When excess water is lost through urine the blood volume is decreased and its osmolarity is increased which stimulates the posterior pituitary to release vasopressin. Vasopressin(ADH) decreases the volume of urine by increasing the facultative absorption of water by kidneys and prevents diuresis. Hence facultative absorption of water from primary urine is influenced by the hormone vasopressin.

So, the correct answer is 'Vasopressin'.

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

Intake of ORS inhibits secretion of

  1. Vasopressin

  2. Oxytocin

  3. Melatonin

  4. Thyroxine
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When excess water is lost through urine the blood volume is decreased and its osmolarity is increased which stimulates the posterior pituitary to release Vasopressin. Vasopressin(ADH) decreases the volume of urine by increasing the facultative absorption of water by kidneys and prevents diuresis. ORS (oral rehydration salt) replaces the lost fluids and essential salts, prevent dehydration and maintain blood volume. Hence Intake of ORS inhibits secretion of vasopressin.

So, the correct answer is 'Vasopressin'.

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 juxta glomerular apparatus is a special region formed by close placement and cellular modification in 

  1. Proximal convoluted tubule and distal convoluted tubule

  2. Loop of Henle and collecting duct

  3. Afferent arteriole and distal convoluted tubule

  4. Afferent arteriole and proximal convoluted tubule
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The juxta glomerular apparatus is a specialised structure made by the glomerular afferent arteriole and the distal convoluted tubule.It is located near the vascular pole of the glomerulus .The main function of juxta glomerular apparatus is to regulate the filteration rate of glomerulus and blood pressure of the body. 

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

A fall in glomerular filtration rate (GFR) activates

  1. Adrenal cortex to release aldosterone

  2. Adrenal medulla to release adrenaline

  3. Posterior pituitary to release vasopressin

  4. Juxta glomerular cells to release renin
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When GFR falls, the juxtaglomerular cells in the kidney detect the change and release renin to activate the RAAS pathway, which helps restore blood pressure and GFR.

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

Antidiuretic hormone is also known as ______________.

  1. Secretin

  2. Vasopressin

  3. Gastrin

  4. Renin
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Antidiuretic hormone (ADH) is also known as vasopressin because of its ability to cause vasoconstriction and raise blood pressure at high concentrations, in addition to its primary role in water reabsorption in the kidneys.