6.2 Heart

Question 1

Parts of the Heart (need to know location)

Answer 1

Pulmonary Artery
Vena Cava
Right Atrium
Semi-lunar valves
Tricuspidd Valve
Right Ventricle
Aorta
Pulmonary Vein
Left Atrium
Bicuspid Valve
Left Ventricle

Question 2

Pulmonary Circulation

Answer 2

The circulation of blood from the heart to the lungs and back (deoxygenated blood, right side of heart)

Question 3

Deoxygenated Blood Flow through Heart:

Answer 3

1. Superior Vena Cava and Inferior Vena Cava - carry deoxygenated blood from the body to the atrium
2. Right Atrium - blood flows through
3. Tricuspid Valve - passes through
4. Right Ventricle - blood flows through
5. Pulmonary Valve (semi-lunar valve) - blood passes through
6. Pulmonary Artery (left) - blood flows through
7. Lungs - blood flows to lungs and becomes oxygenated

Question 4

Systemic Circulation

Answer 4

the circulation of blood from the heart to the body tissues and back (oxygenated blood, left side of heart)

Question 5

Oxygenated Blood Flow through Heart:

Answer 5

1. Lungs - blood flows out of the lungs
2. Left pulmonary Vien
3. Left Atrium - blood flows through
4. Left Ventricle - blood flows through
5. Aortic Valve (semi-lunar valve) - blood passes
6. Aorta - blood flows into and is pumped out of heart
7. Body - blood flows into body

Question 6

Cardiac Accelerator Nerve

Answer 6

stimulates the heart to beat faster by signaling the SA node and is located in the cardiovascular center of the brain

Question 7

Vagus Nerve

Answer 7

reduces the heart rate by signaling the SA node and is located in the cardiovascular center of the brain

Question 8

Epinephrine (adrenalin) hormone

Answer 8

increases the heart rate by stimulating the SA node to emit electrical signals at a faster rate as well as by increasing the conduction speed of impulses generated by both the SA and AV nodes

Question 9

Cardiac Cycle

Answer 9

the complete sequence of events in the heart from the start of one best to the beginning of the following beat

Question 10

Steps in Cardiac Cycle

Answer 10

1. Atrial contraction begins ( atrial systole) .
2. Atria eject blood into ventricles ( atrial systole) .
3. Atrial systole ends; AV valves close (‘lubb’ sound).
4. Isovolumetric contraction of the ventricles occurs ( ventricular systole) .
5. Ventricular ejection occurs.
6. Semilunar valves close (‘dupp’ sound).
7. Isovolumetric relaxation of the ventricles occurs ( ventricular diastole) .
8. AV valves open; passive ventricular filling occurs.

Question 11

Sino-Atrial (SA) node

Answer 11

initiates (starts) each heartbeat and it sets the heart rate, so it is often called the pacemaker. The SA node ‘fires’ (sends electrical signals) at regular intervals to cause the heart to beat with a rhythm of about 60 to 70 beats per minute
- Located in the right atrium

Question 12

Atrio-Ventricular Nodes

Answer 12

is triggered by the SA node and is responsible for the subsequent contractions of the ventricles
- Located in the septum of the heart (between atria and ventricles)

Question 13

Bundle of His

Answer 13

nerve pathway that the AV node sends signals down (for electrical conduction)

Question 14

Perkinje Fibers

Answer 14

supplied with nerves by the bundle of his in order to cause ventricular contraction.