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

The function of kidneys is to

  1. fight against infection

  2. digest the food

  3. purify the blood

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

The primary physiological function of the kidneys is to filter metabolic waste products, excess ions, and toxins from the blood to produce urine, effectively purifying the blood.

Multiple choice

Which of the following statements is/are incorrect?

a. Lymphatic system takes part in the excretory process of the body. b. Lymphatic system protects the body. c. Lymphatic system helps in removing waste products like fragments of dead cells, etc.

  1. only a

  2. only b

  3. only c

  4. only a and c

  5. a, b and c
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the correct answer as this statement is incorrect. Lymphatic system takes part in the nutritive process of the body and not the excretory process.

Multiple choice

Which of the following statements is/are correct?

a. Carbon dioxide and urea are two waste products of the human body that are produced by human cells. b. Some organisms store wastes in body parts. c. The extracellular fluid that flows from body tissues to heart is called blood.

  1. a and b

  2. b and c

  3. a and c

  4. a, b and c

  5. c only
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This is the correct answer as both these statements are correct. Carbon dioxide and urea are two waste products of the human body that are produced by the human cells. Some organisms store wastes in body parts.

Multiple choice

In the process of dialysis used on patients with affected kidneys, the phenomenon involved is

  1. diffusion

  2. absorption

  3. osmosis

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

Dialysis works on the principle of osmosis, where solutes move across a semipermeable membrane from an area of higher concentration to lower concentration. In hemodialysis, waste products like urea and excess salts diffuse across the membrane into the dialysate fluid, while larger molecules like proteins are retained in the blood.

Multiple choice

Which of the following characteristics of insulin makes it usable for assessing glomerular filtration rate?

  1. It is a polysaccharide.

  2. It has high molecular weight.

  3. It has high molecular weight and is insoluble in human tissues.

  4. It has low molecular weight and is unutilized in human tissues.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

As it has low molecular weight, it is easily excreted and being unutilized, it is passed out as such and can be assessed then.

Multiple choice

Which of the following processes is used to clean the blood of a person by separating the waste substances like urea from it?

  1. Hydrolysis

  2. Dialysis

  3. Excretion

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

Dialysis is the medical procedure that artificially cleans blood by removing waste products like urea, creatinine, and excess salts when kidneys fail. It works on the principle of diffusion through a semi-permeable membrane. Hydrolysis is a chemical breakdown process, while excretion is the general biological process.

Multiple choice

The kidneys of human beings are a part of the system for

  1. nutrition

  2. transportation

  3. respiration

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

Kidneys are the primary organs of the excretory system, filtering blood and producing urine to remove metabolic wastes. They are not part of the nutrition system (digestion/absorption), transportation system (circulatory), or respiratory system (gas exchange).

Multiple choice

Kidney is made up of a large number of excretory units called

  1. nephrons

  2. bladders

  3. urethra

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

Nephrons are the microscopic functional units of the kidney, each consisting of a glomerulus and tubule system that filters blood and produces urine. A human kidney contains approximately 1 million nephrons. Bladders store urine, while urethra is the exit tube.

Multiple choice

Endonephric excretion is the one in which

  1. excretory products are thrown out through the skin

  2. yellow coloured blind tube opens in the gut

  3. excretion takes place through kidney

  4. excretion takes place through flame cells
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Endonephric excretion is the one in which yellow coloured blind tube opens in the gut. This enables the animals to prevent loss of water.

Multiple choice

What is the role of liver in excretion?

  1. It excretes a lot of nitrogenous waste in the form of urine.

  2. It converts ammonia into uric acid.

  3. It expels out CO2 gas.

  4. It excretes water from the body.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Liver converts the highly toxic ammonia to soluble and non-toxic uric acid which is later passed out of the body by kidney in the form of urine.