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 34 of 35
- A. iliac vein
- B. iliac artery
- C. temporal artery
- D. Sciatic artery
Explanation: The descending aorta is bifurcated into two vessels called the common iliac arteries (Option B).
Correct answer: iliac artery- A. It sends out electrical impulses to ventrictes to contract.
- B. It is present at upper end of the left atrium
- C. It consists of small number of diffusely oriented cardiac fibers
- D. It sends out electrical impulses to atrial muscles causing both atria to contract.
Explanation: Explanation:SA node or the pacemaker is located in the right atrium and it sends out impulses causing both Atria to contract.
Correct answer: It sends out electrical impulses to atrial muscles causing both atria to contract.- A. It sends out electrical impulses to atrial muscles causing both atria to contract
- B. It consists of small number of diffusely oriented cardiac fibres
- C. It sends out electrical impulses to ventricular muscles causing both ventricles to contract
- D. It is present at upper end of left atrium
Explanation: Option [a] The Sinoatrial node, also known as the pacemaker, is responsible for initiating the heartbeat.
Correct answer: It sends out electrical impulses to atrial muscles causing both atria to contract- A. Ventricular systole
- B. Atrial systole
- C. Diastole
- D. Recovery systole
Explanation: The QRS complex represents depolarization of the ventricles and is followed by ventricular contraction which is collectively known as the…
Correct answer: Ventricular systole- A. Deoxygenated Blood
- B. Oxygenated Blood
- C. Filtered Blood
- D. Non-Filtered Blood
Explanation: [A] Right atrium receives the deoxygenated blood from vena cava after which does into right ventricle and moves through pulmonary artery…
Correct answer: Deoxygenated Blood- A. Smooth Muscles
- B. Papillary Muscles
- C. Intercostal Muscles
- D. Skeletal Muscles
Explanation: This option is the correct answer. The flaps of the tricuspid valves are attached to muscular extensions of the right ventricle known as…
Correct answer: Papillary Muscles- A. Cardiac end of stomach valve
- B. Pyloric sphincter of stomach
- C. Tricuspid valve of heart
- D. Eyelid
Explanation: The chordae tendineae are fibrous cords that attach the flaps of the tricuspid valve to the papillary muscles in the right ventricle of…
Correct answer: Tricuspid valve of heart- A. Heart, activity of smooth muscles and valves
- B. Activity of skeletal muscles, heart and breathing movements
- C. Breathing movements, activity of skeletal muscles and valves
- D. Exercise, breathing movements and heart
Explanation: Option[a] heart has no role in lymph flowOption[b] Heart has no role in lymphOption [c] All mentioned factors affect the flow of lymph in…
Correct answer: Breathing movements, activity of skeletal muscles and valves- A. Subclavian Vein
- B. Renal Vein
- C. Pulmonary Vein
- D. Hepatic Portal Vein
Explanation: a) Subclavian VeinThe subclavian veins are major veins located in the upper chest region, near the collarbone.
Correct answer: Subclavian Vein- A. Superior vena cava
- B. Subclavian Vein
- C. Inferior vena cava
- D. Renal vein
Explanation: Lymph capillaries join to form larger and larger lymph vessels; and ultimately form the thoracic lymph duct, which opens into the…
Correct answer: Subclavian Vein- A. Lymph Nodes
- B. Lymphoid organs
- C. Lymph capillaries
- D. Subclavian vein
Explanation: Lymph eventually returns to the bloodstream by entering the subclavian vein, where it mixes with the blood and is recirculated through the…
Correct answer: Subclavian vein- A. Gallbladder
- B. Liver
- C. Kidneys
- D. Lungs
Explanation: Fibrinogen is a protein produced by the liver, which plays a crucial role in blood clotting by being converted into fibrin during the…
Correct answer: Liver- A. Liver
- B. Spleen
- C. Bone marrow
- D. Heart
Explanation: Blood cells are produced in the red bone marrow from hematopoietic stem cells.
Correct answer: Bone marrow- A. Leukaemia
- B. Polycythemia
- C. Edema
- D. Anemia
Explanation: Polycythemia is characterized by an abnormally high concentration of red blood cells in the bloodstream.
Correct answer: Polycythemia- A. Group A to Group B
- B. Group AB to Group O
- C. Group A to Group O
- D. Group B to Group AB
Explanation: Blood transfusions must be compatible, meaning donor blood antigens should not react with recipient blood antibodies.
Correct answer: Group B to Group AB- A. 5 microns
- B. 6 microns
- C. 7 microns
- D. 8 microns
Explanation: The correct answer is 8 microns. Human capillaries typically have a diameter of about 8 to 10 microns, which is just enough to allow red…
Correct answer: 8 microns- A. 850mm/minute
- B. 900mm/minute
- C. 750mm/minute
- D. 730mm/minute
Explanation: Cerebral circulation refers to the flow of blood through the network of blood vessels supplying the brain.
Correct answer: 750mm/minute- A. 1500 ml
- B. 1600 ml
- C. 1800 ml
- D. 1900 ml
Explanation: Skin blood flow plays a major role in the distribution of thermal energy during exercise.
Correct answer: 1900 ml- A. Arteriosclerosis
- B. Atherosclerosis
- C. Thrombosis
- D. Embolism
Explanation: Atherosclerosis is a condition that specifically involves the buildup of cholesterol and plaque on the artery walls, leading to thickening…
Correct answer: Atherosclerosis- A. Vasa vasorum
- B. Tunica media
- C. Tunica externa
- D. Tunica interna
Explanation: Vasa vasorum is a network of small blood vessels that supply oxygen and nutrients to the walls of larger blood vessels, such as arteries…
Correct answer: Vasa vasorum