Biology

Human Excretion and Kidney Physiology

1,215 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 excreta of lizards and birds contains a white component, which is chemically

  1. urea

  2. uric acid

  3. creatine

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

Birds and reptiles are uricotelic organisms, meaning they excrete nitrogenous waste primarily as uric acid. Uric acid is relatively non-toxic and can be concentrated to a white paste or solid, allowing these animals to conserve water - a critical adaptation for life in dry environments. Urea (mammals) and creatine are different nitrogenous compounds, while precipitated calcium is not involved in nitrogen excretion.

Multiple choice

Vertebrate kidney has __________ as the basic unit.

  1. nephron

  2. ureter

  3. malpighian tubule

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

The nephron is the fundamental structural and functional unit of the kidney, responsible for filtering blood and forming urine. Each kidney contains approximately 1 million nephrons in humans.

Multiple choice

Lewy bodies are found in

  1. brain

  2. plasma

  3. lymph

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

Lewy bodies are abnormal protein aggregates primarily found in brain cells, associated with Parkinson's disease and Lewy body dementia. They are not found in plasma, lymph, or kidneys.

Multiple choice

The biological death of a patient means death of tissues of the

  1. kidney

  2. heart

  3. lungs

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

Biological death refers to brain death - the irreversible cessation of all brain functions, including the brainstem. While death of vital organs like heart, lungs, or kidneys can cause death, the legal and medical definition of biological death centers on brain function.

Multiple choice

The most toxic excretory product is

  1. CO2

  2. amino acids

  3. urea

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

Ammonia is highly toxic and requires large amounts of water for dilution and excretion. Urea is less toxic and can be concentrated. CO2 is eliminated through lungs and amino acids are building blocks, not excretory products. Aquatic organisms excrete ammonia directly, while terrestrial organisms convert it to less toxic urea or uric acid to conserve water.

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.