The Heart and Blood Vessels

• What are the 2 types of circulatory systems?

  The open circulatory system, and the closed circulatory system.
• Name two types of fibrous proteins?

  Collagen and keratin.
• What is the function of a valve?

  To prevent the backflow of blood.
• What is the function of skeletal muscles?

  Help to move blood back to the heart.
• What is said in relation to the size of capillaries?

  They have very thin walls (only 1 cell thick).
• What is the function of capillaries?

  To allow the exchange of materials between the blood and cells of the body.
• Why is the left ventricle thicker than the right ventricle?

  It has to pump blood all around the body.
• What is the function of the bicuspid and tricuspid valves?

  To make sure that blood doesn't flow back into the atria from the ventricles.
• What is the function of the semi-luar valves?

  To make sure that blood doesn't flow back into the heart from the pulmonary artery and aorta.
• What makes the heart a double pump?

  One side pumps blood to the lungs (the pulmonary circuit). The other side pumps blood around the rest of the body (the systemic circuit).
• What is a portal system?

  A blood pathway which begins and ends in capillaries.
• What is the function of the hepathic portal vein?

  Transport glucose and amino acids.
• What is diastole?

  When the heart muscle is relaxed.
• What is systole?

  When the heart is contracting.
• Where is the pacemaker found?

  In the right atrium.
• What is another name for the pacemaker?

  The sino-atrial node / SA node.
• What is the function of the pacemaker?

  To send out electrical impulses which cause the atria to contract.
• What is the function of the coronary arteries?

  Supplies the cardiac muscles with blood.
• What is a pulse?

  The alternate contraction and expansion of arteries.
• What is blood pressure?

  The force blood exerts on the walls of blood vessels.
• What effect does smoking have on the circulation system?

  Nicotine increases the heart rate and blood pressure.
• What effect does diet have on the circulatory system?

  High salt intake raises blood pressure which can cause heart attack.
• What effect does excercise have on the circulatory system?

  Excercise strengthens the heart, including circulation.
• State the location of the sino-atrial node.

  The right atrium.
• Name the transport fluid in humans that doesn't contain RBC's.

  Lymph.
• What feature of RBC's allow them to pass through narrow capillaries?


  They're flexible.
• Why is the blood on the right side of the heart kept separate from the blood on the left?


  The blood on the right side is deoxgenated.
• Where is the coronary artery located?

  In the aorta just above the semi-lunar valves.