Biology ยท General Awareness

Human Circulatory System

818 Questions

The human circulatory system explores the network of blood vessels, heart valves, and structural pathways. Test items often target blood flow sequences and specific vascular functions. Mastering these details is vital for biology preparation.

Heart valves and chambersBlood vessels and venulesArteries of the bodyBlood supply to organsCentral nervous system supply

Human Circulatory System Questions

Multiple choice
  1. prevent backflow of blood

  2. increase surface area

  3. increase blood pressure

  4. absorb blood

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Veins carry blood back to the heart under low pressure; valves are necessary to prevent the backflow of blood due to gravity.

Multiple choice
  1. thinner wall

  2. valves present in them

  3. wide lumen

  4. all of these

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Compared to arteries, veins have thinner walls, wider lumens, and contain valves to facilitate blood return to the heart.

Multiple choice
  1. oxygenated blood to lungs

  2. deoxygenated blood to heart

  3. deoxygenated blood to lungs

  4. oxygenated blood to heart

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The pulmonary artery is unique because it is the only artery that carries deoxygenated blood from the heart to the lungs for oxygenation.

Multiple choice
  1. blood coagulation

  2. homeostasis

  3. clot retraction

  4. hemostasis

  5. vasoconstriction

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The phenomenon of contraction of blood clot after a few minutes of its formation due to contraction of platelets attached to fibrin, leading to the expelling of serum, is called clot retraction.

Multiple choice
  1. the absence of a heart

  2. the absence of blood vessels

  3. blood with a composition different from that of tissue fluid

  4. a higher-pressure circuit through gills than to other organs.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An open circulatory system do not have blood vessels.