Free Circulation MCQs with Answers
695 Circulation MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The circulatory system covers the chambers, valves and conducting pathway of the human heart, along with the cardiac cycle and control of heartbeat. It compares arteries, veins and capillaries by structure and function, and explains how the lymphatic system returns tissue fluid, transports absorbed fats and supports immunity.
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Read the Circulation notesFree MDCAT chapter notes with key terms695 questions · page 13 of 35
- A. Smooth muscles
- B. Cardiac muscles
- C. Skeletal muscles
- D. Voluntary muscles
- E. Both A and C
Explanation: Cardiac muscles are striated muscles found exclusively in the walls of the heart.
Correct answer: Cardiac muscles- A. Solute potential
- B. Hydrostatic pressure
- C. Water potential
- D. Source concentration
- E. Rate of transpiration
Explanation: In the pressure flow theory of phloem transport, the movement of sugars from source (e.g. leaves) to sink (e.g.
Correct answer: Hydrostatic pressure- A. Root Pressure
- B. Leave Pressure
- C. Imbibitions
- D. Transpiration
- E. Transpiration Pull
Explanation: When water evaporates from the aerial parts of the plant, it creates a negative pressure or tension in the xylem vessels, which is known…
Correct answer: Transpiration Pull- A. Cuticular
- B. Lenticular
- C. Stomatal
- D. Leaves
- E. Stem
Explanation: Cuticular transpiration is the loss of water vapour through the cuticle, a waxy, water-repelling layer covering the surface of leaves…
Correct answer: Cuticular- A. A cells
- B. B cells
- C. F cells
- D. T cells
- E. Z cells
Explanation: B cells are a type of white blood cell that recognize antigens and produce antibodies in response to them.
Correct answer: B cells- A. Aorta
- B. Pulmonary trunk
- C. Pulmonary artery
- D. Vena cava
Explanation: The left ventricle of the heart pumps oxygenated blood out of the heart and into the aorta, which is the largest artery in the body.
Correct answer: Aorta- A. 10 - 20
- B. 21 - 30
- C. 31 - 35
- D. 36 - 40
Explanation: Option A: 10-20 hours: This is the lifespan of monocytes, a type of white blood cell that fights infection.
Correct answer: 10 - 20- A. Karyolymph
- B. Nucleoplasm
- C. Protoplasm
- D. Serum
Explanation: Option A: Karyolymph is the fluid portion of the nucleus of a cell. It is made up of water, salts, and dissolved proteins.
Correct answer: Serum- A. Red color
- B. Blue color
- C. Reddish purple color
- D. Reddish blue color
Explanation: Blood containing carbon dioxide (CO2) is reddish purple in color. This is because CO2 binds to hemoglobin, a protein in red blood cells…
Correct answer: Reddish purple color- A. Hypoxia
- B. Exercise
- C. Sleep
- D. Pregnancy
- E. Anemia
Explanation: During sleep, cardiac output typically decreases compared to wakefulness.
Correct answer: Sleep- A. Liver
- B. Spleen
- C. Bone marrow
- D. Thymus
Explanation: The answer is bone marrow. In adults, red blood cells (RBCs) are formed in the red bone marrow of bones.
Correct answer: Bone marrow- A. Heparin
- B. Histamine
- C. Antibody
- D. Both A and B
Explanation: The correct answer is both A and B. Basophils are a type of white blood cell that are involved in the immune system.
Correct answer: Both A and B- A. Right atrium
- B. Left atrium
- C. Right ventricle
- D. Left ventricle
Explanation: The oxygenated blood is brought back to the heart by the pulmonary veins which enter the left atrium.
Correct answer: Left atrium- A. Leukemia
- B. Edema
- C. Thalassemia
- D. Atherosclerosis
Explanation: Leukaemia is a type of cancer that results in the body making too many abnormal white blood cells.
Correct answer: Leukemia- A. Hypertonic
- B. Hypotonic
- C. Isotonic
- D. Heterotonic
Explanation: When the concentration of the external medium is equal to the concentration of the internal medium of the cell is called an isotonic…
Correct answer: Isotonic- A. They do not suffer from anemia.
- B. They receive more blood than other people.
- C. Their blood contains neither A nor B antibodies.
- D. Their blood contains both A and B antigens
Explanation: People with type AB+ blood are universal recipients because they have no antibodies to A, B or Rh in their blood and can receive red blood…
Correct answer: Their blood contains neither A nor B antibodies.- A. Fishes and amphibians
- B. Amphibians and birds
- C. Birds and mammals
- D. Mammals and fishes
Explanation: Juxtamedullary nephrons are found only in birds and mammals, and have a specific location: medullary refers to the renal medulla, while…
Correct answer: Birds and mammals- A. Cellular pathway
- B. Symplast pathway
- C. Apoplast pathway
- D. Water pathway
Explanation: Movement from cell to cell through plasmodesmata is a symplast pathway.
Correct answer: Symplast pathway- A. Natural killer cells
- B. Interferons
- C. Antigen-presenting cells
- D. Vaccines
Explanation: Antigen-presenting cells (APCs) phagocytose antigens and present those antigens on the surface of themselves so that they can be…
Correct answer: Antigen-presenting cells- A. Brain
- B. Heart
- C. Blood
- D. Tissues
Explanation: Small amounts of glycogen are also found in other tissues and cells, including the kidneys, red blood cells, white blood cells, and glial…
Correct answer: Blood