Week 2; L4, L5

Question 1

What is the function of the right atrium & ventricle?

What is the function of the left atrium & ventricle?

Answer 1

Right atrium & ventricle: delivery of deocynated blood to lungs.

Left atrium & ventricle: delivery of ocygenated blood to the body.

Question 2

How do you call the 4 valves?

Answer 2

Mitral (left) and tricuspid (right) vales betweeen atrium and ventricle.
The aortic and pulmonary valve between ventrucle and artery.

Question 3

How do you call the cardiac muscle?

Difference sympathic & parasympathetic?

Answer 3

How do you call the cardiac muscle? The myocardium.

Sympathic: accelerates the rate; parasympathetic: slows down the rate.

Question 4

Cardiac cycle consists of 2 phases: systole and diastole.

Answer 4

Systole: the ventricles are full of blood and begin to contract. The mitral and tricususpid valves close (between atria and ventricles). Blood is ejected through the pulmonary and aortic valves.

Diastole: blood flows into the atria and through the open mitral and tricuspid valves into the ventricles.

Question 5

Steps of the cardiac condiction system

Answer 5

Sinoatrial (SA) node
Atrioventricular (AV) node
Bundle of His
Left and right bundle branches
Purkinje fibers

Question 6

Steps of nodal myocite depolarization

Answer 6

1. Na+ inward funny current (if) determines a spontaneous increase of the trans-membrane potential to -50 mV, activating the Ca2+ channels.
2. Depolarization; Ca2+ inflow though the open Ca channels.
3. Repolarization; K+ channels open (outflow) and Ca2+ channels closed.

Question 7

What does it mean?

• P wave
• QRS complex
• T wave

Answer 7

• P wave: atrial depolarization
• QRS complex: ventricular depolarization
• T wave: ventricular repolarization