Heart Beat And Heart Rate

Question 1

What does myogenic mean?

Answer 1

The signal for cardiac compression arises within the heart tissue itself

Question 2

Where is the signal for a heartbeat initiated?

Answer 2

Initiated by cardiomyocytes

Question 3

What are the specialized cluster of cardio myocytes within the wall of the right atrium called?

Answer 3

Sinoatrial node

Question 4

How many cardiac contractions per minute does the sinoatrial node trigger?

Answer 4

60 to 100

Question 5

What is the secondary pacemaker called?

Answer 5

AV node

Question 6

How many cardiac contractions does the AV node maintain?

Answer 6

40 to 60 BPM

Question 7

What is the final tertiary pacemaker?

Answer 7

Bundle of His

Question 8

How many contractions can the bundle of His maintain?

Answer 8

30 to 40 BPM

Question 9

What is fibrillation?

Answer 9

Irregular and uncoordinated contraction of the heart muscle

Question 10

What is defibrillation?

Answer 10

A controlled electrical current that reestablish his normal sinus rhythm

Question 11

What leads to there being two Heart sounds?

Answer 11

A delay between the atrial and ventricular contractions due to electrical conduction

Question 12

What is the normal resting adult human heart rate?

Answer 12

60 to 90 BPM

Question 13

What can trigger rapid changes of the basal heart rate?

Answer 13

Nerve signals from the brain

Question 14

What can trigger less rapid changes in the basal heart rate?

Answer 14

Endocrine signals

Question 15

What controls the pacemaker?

Answer 15

The autonomic system of the brain specifically the medulla oblongata also known as the brainstem

Question 16

What does a sympathetic nerve do?

Answer 16

Releases the neurotransmitter noradrenaline (a.k.a. norepinephrine) to increase heart rate

Question 17

What does the parasympathetic/vagus nerve do?

Answer 17

Releases the neurotransmitter acetylcholine to decrease heart rate