Cardiac Anatomy and Physiology

Question 1

What is the meaning of bifurcate?

Answer 1

Splitting of vessels

Question 2

What are the features of cardiac muscle?

Answer 2

-Striated
-Intercalated discs
-Gap junctions
-Mulit- nucleated.

Question 3

What is the pericardium?

Answer 3

This protects the heart from movement, heat etc.

Question 4

What is the purpose of pericardial fluid?

Answer 4

This allows the layers to slide over each other (however too much fluid is dangerous).

Question 5

Which valves are semilunar (SL)?

Answer 5

The aortic and pulmonary valves.

Question 6

Which valves are atrioventricular (AV)?

Answer 6

The mitral and tricuspid valves.

Question 7

What is the equation for cardiac output?

Answer 7

Cardiac output= Heart rate x Stroke volume

Question 8

Where is the moderator band?

Answer 8

Right ventricle.

Question 9

What is the most anterior valve?

Answer 9

The pulmonary valve.

Question 10

Where is the Ostia of the coronary sinus?

Answer 10

The right atrium.

Question 11

How many pulmonary veins are there?

Answer 11

4

Question 12

What are the 3 layers of the pericardium?

Answer 12

-Outer fibrous layer (protects and anchors)
-2 layered serous layer (visceral- also known as epicardium and parietal)

Question 13

What is the function of the myocardium?

Answer 13

Thick bundles of cardiac muscle- the layer that actually contracts.

Question 14

What is the function of the endocardium?

Answer 14

Sheet of endothelium that lumens the heart chambers.

Question 15

Which are the receiving chambers?

Answer 15

The atria.

Question 16

What do the atria do?

Answer 16

They assist with filling ventricles.
Blood flows to atria under low pressure from veins, continues on to fill ventricles.

Question 17

Which are the discharging chambers?

Answer 17

The thick walled ventricles.

Question 18

What happens when the ventricles contract?

Answer 18

Blood is propelled out of heart and into circulation.

Question 19

What is the interatrial septum?

Answer 19

This is the septum that divides the atria longitudinally.

Question 20

What is the inter ventricular septum?

Answer 20

Septum that divides the ventricles.

Question 21

Which side of the heart works as a pulmonary circuit pump?

Answer 21

The right side.

Question 22

What is pulmonary circulation?

Answer 22

This receives oxygen poor blood from veins through superior and inferior vena cava. Pumps it out through the pulmonary trunk (splits into right and left pulmonary arteries that carry blood to lungs where oxygen is picked up). Oxygen rich blood drains from lungs and is received in left side of heart through 4 pulmonary veins.

Question 23

What is systemic circulation?

Answer 23

Oxygen rich blood returned to left atrium flows to left ventricle and leaves heart through aorta to to deliver blood to tissues in the body. Oxygen poor blood then comes back from tissues back to right atrium.

Question 24

How many cusps does the mitral valve have?

Answer 24

2.

Question 25

How many cusps does the tricuspid valve have?

Answer 25

3.

Question 26

What are chordae tendinae?

Answer 26

These are small chords that anchor the cusps to the walls of the ventricles.

Question 27

What happens to the AV cusps when the heart is relaxed (blood filling chambers)?

Answer 27

They hang limply into the ventricles.

Question 28

What happens to the AV cusps when the ventricles contract?

Answer 28

Pressure inside ventricles start to rise- forces AV cusps upward closing the valves (chordinae tendinae tighten and anchor cusps in closed position).

Question 29

How many cusps does each semilunar valve have?

Answer 29

3.

Question 30

What happens to SL valves when ventricles contracting?

Answer 30

Forcing blood out of the heart so they are forced open (flattened against wall of arteries).

Question 31

What happens to the SL valves when the ventricles relax?

Answer 31

Blood begins to flow backwards towards the heart and the cusps fill with blood and close.

Question 32

Position of valves when ventricles contracting?

Answer 32

AV valves closed and SL valves open.

Question 33

Position of valves when ventricles relaxing?

Answer 33

AV valves open and SL valves closed.

Question 34

What is Tachycardia?

Answer 34

Rapid heart rate.

Question 35

What is Bradycardia?

Answer 35

Heart rate that is slower than normal.

Question 36

What is systole?

Answer 36

This is heart contraction.

Question 37

What is diastole?

Answer 37

This is heart relaxation.

Question 38

What does cardiac cycle mean?

Answer 38

Refers to events of one complete heartbeat (both atria and ventricles contract and then relax).

Question 39

What is atrial diastole?

Answer 39

Ventricular filling- pressure on heart is low, AV valves open and blood is flowing through atria to ventricles. SV valves are closed.

Question 40

What is atrial systole?

Answer 40

Ventricles remain in diastole as atria contract- forcing blood into ventricles to complete ventricular filling.

Question 41

What is isovolumetric contraction?

Answer 41

Atrial systole ends and ventricular systole begins- rise in intraventricular pressure closes AV valves (preventing back flow).

Question 42

What is ventricular systole?

Answer 42

Ventricles continue to contract, causing intraventricular pressure to surpass pressure in arteries. Causes SL valves to open and blood ejected from ventricles (move from high to low pressure). Atria are relaxed and filling with blood.

Question 43

What is isovolumetric relaxation?

Answer 43

Ventricular diastole begins, pressure below major arteries, SL valves close to prevent back flow. Ventricles are closed chambers and pressure continues decreasing. Atria have been in diastole (filling with blood). When atrial pressure increases above ventricular pressure, AV valves open and cycle repeats.