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 31 of 35
- A. Diffusion
- B. Facilitated diffusion
- C. Passive transport
- D. Active transport
Explanation: The transport of minerals from the soil to the epidermal cells of roots via carrier protein molecules along their concentration gradient…
Correct answer: Facilitated diffusion- A. Normal saline
- B. Distilled water
- C. Glucose solution
- D. Away from sunlight
Explanation: To attain maximum turgidity of a plant cell, it should be placed in a hypotonic solution, such as distilled water.
Correct answer: Distilled water- A. Cohesion
- B. Adhesion
- C. Tension
- D. Attraction
Explanation: Hydrogen bonding between water molecules produces cohesion. Cohesion refers to the attractive forces that hold water molecules together…
Correct answer: Cohesion- A. Plant B
- B. Plant C
- C. Plant D
- D. Plant A
Explanation: Rate of transpiration is directly proportional to light, temperature and wind.
Correct answer: Plant D- A. Sink to source
- B. Sink to sink
- C. source to sink
- D. Source to source
Explanation: Translocation of sucrose in plants primarily occurs from source to sink.
Correct answer: source to sink- A. Preasure flow theory
- B. Diffusion
- C. Imbition
- D. Ascent of sap
Explanation: The widely accepted theory that explains the transport of organic solutes in plants is the Pressure Flow Theory, also known as the Mass…
Correct answer: Preasure flow theory- A. Diffusion
- B. Active transport
- C. Passive transport
- D. Facilitated diffusion
Explanation: Loading of sucrose from companion cells to sieve tube cells involves active transport.
Correct answer: Active transport- A. Tears
- B. Mucus membrane
- C. WBCs
- D. Ciliated cells
- E. RBCs
Explanation: Option E is correct.RBCs have no role in immunity. RBCs (red blood cells) do not protect the body against the entrance of germs.
Correct answer: RBCs- A. Lymphocytes
- B. Platelets
- C. Monocytes
- D. Red blood cells
Explanation: Option D is correct.Yes, red blood cells (RBCs) are the only type of blood cells that have a biconcave disc shape.
Correct answer: Red blood cells- A. Monocytes
- B. Lymphocytes
- C. Neutrophils
- D. Thrombocytes
Explanation: Option D is correct.Thrombocytes do not play a role in developing immunity.
Correct answer: Lymphocytes- A. four months
- B. Five months
- C. Two months
- D. One month
Explanation: The average life span of a red blood cell (RBC) is about 120 days or four months.
Correct answer: four months- A. Right atria
- B. Left atria
- C. Right ventricle
- D. Left ventricle
Explanation: Yes, the left ventricle has the thickest walls of the four chambers of the heart.
Correct answer: Left ventricle- A. Right atrium
- B. Left atrium
- C. Right ventricle
- D. Left ventricle
Explanation: Oxygenated blood is supplied to all body parts from the left ventricle. The left ventricle is the main pumping chamber of the heart.
Correct answer: Left ventricle- A. It arises in the vessels of the brain
- B. It drains the entire body above the diaphragm
- C. It empties its contents into the subclavian vein
- D. It carries blood into the lymphatic system
Explanation: The thoracic duct, also known as the left lymphatic duct, is the largest lymphatic vessel in the human body.
Correct answer: It empties its contents into the subclavian vein- A. I only
- B. III only
- C. I and II
- D. II and III
Explanation: A ventricular septal defect allows oxygen-rich blood to mix with oxygen-poor blood, leading to several issues.
Correct answer: I and II- A. Is closed
- B. Is opened
- C. is bearing the greatest pressure
- D. Shows a continuous change in the diameter
Explanation: When the cuff pressure drops below diastolic pressure, the artery is no longer compressed, blood flow becomes laminar, and Korotkoff…
Correct answer: Is opened- A. Atrium
- B. Dorsal aorta
- C. Ventral aorta
- D. Sinus venosus
Explanation: In the circulatory system of a fish, the heart operates in a single circuit, meaning that blood passes through it once per cycle.
Correct answer: Sinus venosus- A. Liver and Gall bladder
- B. Spleen and Thymus gland
- C. Thyroid and Parathyroid glands
- D. Lymph vessels and Bone marrow
Explanation: The correct answer is Option D: lymph vessels and bone marrow. Bone marrow is a key component in the production of lymphocytes, which are…
Correct answer: Lymph vessels and Bone marrow- A. Neck region
- B. Axilla
- C. Groin
- D. Spleen
Explanation: Lymph nodes are small, bean-shaped structures located throughout the body, including the neck, armpits, groin, and other areas.
Correct answer: Spleen- A. 140-150
- B. 115-125
- C. 72-80
- D. None of these
Explanation: A normal resting adult pulse is commonly about 72 beats/min, and the listed 72-80 beats/min range falls within the usual resting range.
Correct answer: 72-80