Cardiovascular System

Question 1

Describe venous flow.

Answer 1

• Venous blood is under LOW pressure.
• Venous return is aided by VALVES within the veins. (ensures 1 way flow)

Question 2

What is an artery?

Answer 2

• Stronger than a vein.
• Thick, muscular walls
• Small lumen
• Contains elastin
• Pushes blood AWAY from the heart to the body.
• Carry blood under HIGH pressure

Question 3

What is a vein?

Answer 3

• Thin walls
• Large lumen
• Carries blood under low pressure
• Carries blood towards the heart
• Contains valves (prevent back flow of blood)

Question 4

Where is the location of the heart?

Answer 4

• Lies in thoracic cavity
• Middle of media sternum
• Lies more to the LEFT

Question 5

What is the function of the heart?

Answer 5

• Act as a pump to facilitate blood flow around the cardiovascular system.

Question 6

Where does the heart get its own blood supply from?

Answer 6

• Left and right coronary arteries

Question 7

What are the 4 chambers of the heart?

Answer 7

• Right atrium, Left atrium
• Right ventricle, Left ventricle

Question 8

What are the 3 main functions of the cardiovascular system?

Answer 8

• Maintain homeostasis
• Pump oxygenated and nutrient rich blood to body
• Pump deoxygenated blood back from tissues to disposal of waste products

Question 9

Where does the right atrium receive deoxygenated blood from?

Answer 9

Systemic veins

Question 10

Where does the left atrium receive oxygenated blood from?

Answer 10

Pulmonary veins

Question 11

What are atria?

Answer 11

• Thin-walled chambers that receive blood from the veins.

Question 12

What are ventricles?

Answer 12

• Thick-walled chambers that forcefully pump blood out of the heart via arteries.

Question 13

Why does the thickness of the heart chambers walls differ?

Answer 13

• Due to different variations in the amount of myocardium present.

Question 14

What is the outer layer of the heart called?

Answer 14

Pericardium

Question 15

What is the pericardium?

Answer 15

• Outermost layer of the <3
• Consists of the parietal (outer) and visceral (inner) layers

Question 16

What is the myocardium?

Answer 16

• Cardiac muscle layer
• Forms bulk of the <3
• Where contraction occurs

Question 17

What is the fibrous skeleton of the heart?

Answer 17

• Interlacing layer of connective tissue
  (criss-crossing)

Question 18

What is the endocardium?

Answer 18

• Endothelial layer of the myocardial surface

Question 19

In there pericardium, what does the pericardial cavity contain?

Answer 19

Pericardial fluid

Question 20

What layer forms the BULK of the heart?

Answer 20

• Myocardium

Question 21

What are the atrioventricular (AV) valves also known as?

Answer 21

• Tricuspid and Bicuspid

Question 22

What are the semilunar valves?

Answer 22

• The valves at the base of the large vessels leaving the ventricles.

Question 23

What is the pulmonary semilunar valve?

Answer 23

• The valve between the right ventricle and the pulmonary trunk.

Question 24

What is the aortic semilunar valve?

Answer 24

• The valve between the left ventricle and the aorta.

Question 25

What is the LUBB sound?

Answer 25

- AV valves CLOSING

Question 26

What is the DUBB sound?

Answer 26

- Pulmonary and aortic semilunar valves closing.

Question 27

When does the LUBB sound occur?

Answer 27

- During ventricular systole

Question 28

When does the DUBB sound occur?

Answer 28

- During ventricular diastole

Question 29

Why do the AV valves close when the ventricles contract?

Answer 29

- To prevent back flow of blood into the atria. (LUBB)

Question 30

Why do the semilunar valves close when the ventricles relax?

Answer 30

- To prevent the back flow of blood into the ventricles. (DUBB)

Question 31

Describe the direction of blood flow through the heart.

Answer 31

- De-oxygenated blood enters the right side of the heart via the superior + inferior vena cava - It flows through the right atrium to the left ventricle and travels to the lungs via the pulmonary artery. - The blood becomes re-oxygenated at the lungs. - Re-oxygenated blood enters the heart via the pulmonary vein and enters the left atrium through to the left ventricle. - The blood is then pumped out of the aorta to the rest of the body.