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 33 of 35
- A. Prothrombin
- B. Lipoprotein
- C. Albumin
- D. Iron
Explanation: Serum albumin accounts for 55% of blood proteins and is a major contributor to maintaining the osmotic pressure of the plasma to assist in…
Correct answer: Albumin- A. 100 days
- B. 110 days
- C. 120 days
- D. 130 days
Explanation: This is a standard answer. Lifespan of RBCs is approximately 120 days.This option c suggests that the life span of red blood cells (RBCs)…
Correct answer: 120 days- A. A+ve
- B. O-ve
- C. AB+ve
- D. O+ve
Explanation: O negative donors are often called 'universal donors' because anyone can receive the red blood cells from their donations.
Correct answer: O-ve- A. Liver
- B. Large intestine
- C. Stomach
- D. Gall bladder
Explanation: Explanation for this question will be added soon.
Correct answer: Large intestine- A. Ventricular systole
- B. Ventricular diastole
- C. Atrial systole
- D. Atrial diastole
- E. Both during atrial systole and atrial diastole
Explanation: Explanation for this question will be added soon.
Correct answer: Ventricular systole- A. Purkinje fibers
- B. AV bundle
- C. Sinoatrial node
- D. Bundle of His
Explanation: The impulse starts in a small bundle of specialised cells located in the right atrium, called the SA node.
Correct answer: Sinoatrial node- A. Oxygenated
- B. Deoxygenated
- C. Oxygenated and Deoxygenated
- D. None
Explanation: The left side pumps oxygenated blood (high in oxygen and low in carbon dioxide) to the organs of the body.
Correct answer: Deoxygenated- A. Aorta
- B. Pulmonary veins
- C. Pulmonary artery
- D. Dorsal aorta
Explanation: The pulmonary artery leaves the right ventricle and takes blood to the lungs.
Correct answer: Pulmonary artery- A. Left ventricle
- B. Right ventricle
- C. Left atrium
- D. Right atrium
Explanation: The aorta is the largest vessel within the human body. It originates from the left ventricle of the heart anterior to the pulmonary artery…
Correct answer: Left ventricle- A. Left atrium
- B. Left ventricle
- C. Right ventricle
- D. Right atrium
Explanation: The left ventricle is the heart chamber that pumps oxygenated blood into the aorta, which then carries it to the rest of the body.
Correct answer: Left ventricle- A. Reticulocytes
- B. Erythrocyte
- C. Basiophilic erythroblasts
- D. None of these
Explanation: Option A: Reticulocytes are immature red blood cells that still contain remnants of ribosomes and RNA.
Correct answer: Erythrocyte- A. Lymphoid masses
- B. Lymph vessels
- C. Spleen
- D. Lungs
Explanation: The four organs of the lymphatic system are bone marrow, spleen, thymus, lymph nodes, and lymphatic vessels.
Correct answer: Lungs- A. Eosinophils
- B. Neutrophils
- C. Monocytes
- D. Basophils
Explanation: Explanation:Heparin prevents blood clots and is released by Basophils. Hence, D is the correct option.
Correct answer: Basophils- A. Albumin
- B. Globulin
- C. Fibrinogen
- D. Prothrombin
Explanation: Option [A] The plasma proteins maintain colloidal osmotic pressure of blood.
Correct answer: Albumin- A. Lymphocytes
- B. Monocyte
- C. Eosinophils
- D. Basophils
Explanation: Option [A] Lymphocytes are the agranulocytes .They create antibodies to fight against bacteria, viruses, and other potentially harmful…
Correct answer: Monocyte- A. External pressure applied becomes greater than the systolic pressure
- B. External pressure applied is equal to systolic pressure
- C. External pressure applied is less than the systolic pressure
- D. External pressure applied is zero
Explanation: The correct answer is A. External pressure applied becomes greater than the systolic pressure.
Correct answer: External pressure applied becomes greater than the systolic pressure- A. Prothrombin
- B. Fibrinogen
- C. Immunoglobulin
- D. Globulin
- E. Both A and B
Explanation: Prothrombin is a protein made by the liver. Prothrombin helps blood to clot.
Correct answer: Both A and B- A. Aorta
- B. Arteries
- C. Veins
- D. Both options A and B
Explanation: The elastic fibres are essential in the recoil and the stretch of the blood vessel in order to survive high blood pressure.
Correct answer: Veins- A. Arteries
- B. Capillaries
- C. Veins
- D. Arterioles
Explanation: Valves in veins are one-way(semi lunar) flaps that help prevent blood from flowing backward in the circulatory system.
Correct answer: Veins- A. Heart directly
- B. Pre-capillary sphincters
- C. Meta-arterioles
- D. Valves
Explanation: The flow of blood in the capillaries is primarily adjusted by pre-capillary sphincters, which regulate the entry of blood into the…
Correct answer: Pre-capillary sphincters