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 26 of 35
- A. Arteriosclerosis
- B. Arthritis
- C. Aneurysm
- D. Both (b) and (c)
Explanation: Arteriosclerosis is the hardening of arteries and arterioles due to thickening of the fibrous tissue, and the consequent loss of…
Correct answer: Arteriosclerosis- A. 120 mm Hg and 80 mm Hg
- B. 50 mm Hg and 80 mm Hg
- C. 80 mm Hg and 80 mm Hg
- D. 70 mm Hg and 120 mm Hg
Explanation: It is correct. Systolic pressure of 120 mm Hg is considered normal and diastolic pressure of 80 mm Hg is also considered normal.
Correct answer: 120 mm Hg and 80 mm Hg- A. Forming RBCs
- B. Destroying bacteria
- C. Forming WBCs
- D. Forming antibodies
Explanation: Formation of WBCs, antibodies and destruction of bacteria occur in lymph glands while formation of RBCs occur in bone marrow.
Correct answer: Forming RBCs- A. Atmospheric pressure
- B. High pressure
- C. Low pressure
- D. All of these
Explanation: Veins carry blood at low pressure as compared to blood carried by arteries.
Correct answer: Low pressure- A. Humans
- B. Arthropods
- C. Rabbits
- D. Rats
Explanation: The neurogenic heart is a characteristic feature of most arthropods and some annelids.
Correct answer: Arthropods- A. The mitral valve is closed
- B. The semilunar valves at the base of the aorta get closed
- C. The tricuspid valve is opened
- D. The mitral valve is opened
Explanation: Therefore, the correct answer is B) The semilunar valves at the base of the aorta get closed, as their closure contributes to the 'dub'…
Correct answer: The mitral valve is closed- A. Sino-atrial Node (SAN)
- B. Atrioventricular Node (AVN)
- C. Purkinje Fibres
- D. Papillary Muscle.
Explanation: Therefore, the correct answer is B) atrio-ventricular node (AVN), as it is responsible for transmitting the electrical signals from the…
Correct answer: Sino-atrial Node (SAN)- A. RBC
- B. RBC and Leucocytes
- C. Leucocytes
- D. Lymphocytes
Explanation: Therefore, the correct answer is B) red blood cells (RBC) and leukocytes, as these cells are both formed in the bone marrow.
Correct answer: RBC and Leucocytes- A. Thrombocytes
- B. Monocytes
- C. Erythrocytes
- D. Lymphocytes
Explanation: Therefore, the correct answer to the question "Component of blood responsible for producing antibodies is" is D) lymphocytes.
Correct answer: Lymphocytes- A. Haemocytes
- B. Parietal Cells
- C. Endothelial Cells
- D. Oxyntic Cells
Explanation: Therefore, the correct answer to the question "The wall of blood capillary is formed of" is C) Endothelial cells.
Correct answer: Endothelial Cells- A. Tunica media and tunica externa form a single-coat
- B. Tunica interna and tunica media form a single coat
- C. Tunica interna, tunica media, and tunica externa are thin
- D. Tunica media is a thin coat
Explanation: Therefore, the correct answer to the question "A vein possesses a large lumen because" is D) tunica media is a thin coat.
Correct answer: Tunica media is a thin coat- A. Pulmonary
- B. Cardiac
- C. Hepatic
- D. Systemic
Explanation: The pulmonary artery carries the blood from the right ventricle of the heart to the lungs for oxygenation so it carries deoxygenated blood.
Correct answer: Pulmonary- A. Cause delayed clotting
- B. Prevent clotting
- C. Cause immediate clotting
- D. Prevent destruction of hemoglobin
Explanation: Clotting requires calcium, without it clotting will not occur.
Correct answer: Prevent clotting- A. Sinus venous and right atrium
- B. The right atrium and right ventricle
- C. left ventricle and left atrium
- D. left ventricle and aorta.
Explanation: The tricuspid valve is found between the right atrium and the right ventricle.
Correct answer: The right atrium and right ventricle- A. No WBCs
- B. No proteins
- C. No RBCs
- D. None of the above
Explanation: The lymph is a whitish fluid which is derived from the interstitial fluid that circulates throughout the lymphatic system.
Correct answer: No RBCs- A. Frog
- B. Cow
- C. Camel
- D. Cockroach
Explanation: RBCs do not occur in the blood of cockroaches. The circulatory system of cockroaches is of open type.
Correct answer: Cockroach- A. Flaccid
- B. Turgid
- C. Collapsed
- D. Ruptured
Explanation: When cells become flaccid they close. Hence, the transpiration rate decreases.
Correct answer: Flaccid- A. Water
- B. ATPs
- C. Carbohydrates
- D. Proteins
Explanation: Answer is "ATPs"Explanation: Companion cells supply ATP and proteins to sieve tubes.
Correct answer: ATPs- A. Evaporation
- B. Transpiration pull
- C. Guttation
- D. Wilting
Explanation: Answer is "Transpiration pull"Explanation: The main force that draws water from the soil for plant is caused by a process called…
Correct answer: Transpiration pull- A. Ascent of sap
- B. Guttation
- C. Plasmolysis
- D. Deplasmolysis
Explanation: Answer is "Plasmolysis"Explanation: Plasmolysis can be defined as the shrinkage of protoplast due to exosmosis of water.
Correct answer: Plasmolysis