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

What is meant by renal threshold value?

  1. Volume of urine formed per day by kidney

  2. Concentration of a substance in blood above which the kidneys begin to remove it

  3. Amount of urine that kidneys can hold

  4. The maximum life of a kidney
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The concentration of a substance in blood above which the kidneys begin to remove it is called the renal threshold value.

Multiple choice

What is meant by medullary interstitium?

  1. It is the medullary extension of the renal cortex in between the renal pyramids.

  2. It is the functional space in the kidney beneath the individual fibres.

  3. It is a dense fibrous connective tissue sheath which surrounds the kidney.

  4. It is the inner layer of the kidney which contains some portions of the renal tubules and most of the collecting duct tubules of the kidney.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The medullary interstitium is the functional space in the kidney beneath the individual filters (glomeruli), which are rich in blood vessels. The interstitium absorbs fluid recovered from urine.

Multiple choice

What is the function of Bowman's capsule?

  1. It reabsorbs glucose, amino acids, phosphate, potassium, urea and other organic solutes from the filtrate.

  2. It is the functional unit of kidney.

  3. It filters blood to form urine.

  4. It makes urine more concentrated.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Bowman's capsule performs the first step in the filtration of blood to form urine. It allows liquids and small solid particles to pass through but prevents larger structures (e.g. blood cells) from passing through.

Multiple choice

The urine consists of

  1. 95% water

  2. 2.5% Urea

  3. 2.5% other waste products

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The urine consists of 95% water, 2.5% urea and 2.5% other waste products.

Multiple choice

The wastes dissolved in water are removed as

  1. Feces

  2. Urine

  3. Urea

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

When the blood reaches the two kidneys, it contains both useful and harmful substances. The useful substances are absorbed back into the blood. The wastes dissolved in water are removed as urine.

Multiple choice

Kidneys of adult reptiles are

  1. Protonephric

  2. Mesonephric

  3. Metanephric

  4. All of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Metanephric kidney is found in reptiles. Part of it develops from the caudal portion of the intermediate cell mass or nephrotome, the remaining portion is derived from a bud of the mesonephric duct.

Multiple choice

The functional kidney of frog tadpole is

  1. Pronephros

  2. Archinephros

  3. Metanephros

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

The functional kidney of a frog tadpole is pronephros (head kidney) developed from nephrotomes in the anterior regions.

Multiple choice

Urine is temprorily stored in

  1. Kidneys

  2. Urinary bladder

  3. Ureters

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

The urinary bladder is the organ that collects urine excreted by the kidneys before disposal by urination. A hollow muscular, and distensible (or elastic) organ, the bladder sits on the pelvic floor. Urine enters the bladder via the ureters and exits via the urethra.

Multiple choice

Which of the following is not a secretion of kidney?

  1. Calcitriol

  2. Antidiuretic

  3. Renin

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

Antidiuretic hormone is secreted from the posterior pituitary. Within hypothalamic neurons, the hormone is packaged in secretory vesicles with a carrier protein called neurophysin, and both are released upon hormone secretion.

Multiple choice

Which among the following is not an excretory organ?

  1. Skin

  2. Lungs

  3. Kidneys

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

The gallbladder is a small pear-shaped organ that stores and concentrates bile. The gallbladder is connected to the liver by the hepatic duct. It is approximately 3 to 4 inches (7.6 to 10.2 cm) long and about 1 inch (2.5 cm) wide. It is not an excretory organ.

Multiple choice

Which of the following is the innermost part of the kidney?

  1. The renal fascia

  2. The renal cortex

  3. The renal medulla

  4. The renal pyramids

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The renal medulla is the innermost part of the kidney. The renal medulla is split up into a number of sections, known as the renal pyramids. Blood enters into the kidney via the renal artery which then splits up to form the arcuate arterioles