CVS Physiology

Question 1

Are pumps in series or parallel?

Answer 1

Series

Question 2

Are vascular beds in series or parallel?

Answer 2

Parallel

Exceptions - hypothalamus, anterior pituitary gland, gut and liver

Question 3

Describe the conducting system of the heart

Answer 3

Sinoatrial node 
Annulus fibrosis
Atrioventricular node
Bundle of His
Purkinje fibres

Question 4

Sinoatrial node

Answer 4

Pacemaker

0.5m/sec

Question 5

Annulus fibrosis

Answer 5

Non-conducting

Question 6

Atrioventricular node

Answer 6

Delay box

0.05m/sec

Question 7

Bundle of His and purkinje fibres

Answer 7

Rapid

5m/sec

Question 8

Describe the embryological development of the heart

Answer 8

Truncus arteriosis
Bulbis cordis
Ventricle
Atrium
R and L horns of sinus venosis

Question 9

Aortic arch derivatives

Answer 9

1 - maxillary arteries
2 - maxillary arteries
3 - common carotid artery
4L - arch of aorta (distal)
4R - R subclavian artery
5 - never forms
6L - left pulmonary artery
6R - right pulmonary artery

Question 10

P wave

Answer 10

Atrial depolarisation

Question 11

QRS complex

Answer 11

Ventricular depolarisation

Question 12

T wave

Answer 12

Ventricular repolarisation

Question 13

How do you measure HR from an ECG?

Answer 13

Count the R waves in 30 squares and x6

Question 14

Diastole

Answer 14

Filling phase

Question 15

Systole

Answer 15

Contraction

Question 16

1st heart sound

Answer 16

Mitral and tricuspid closing

Question 17

2nd heart sound

Answer 17

Aortic and pulmonary closing

Question 18

How is BP controlled short term?

Answer 18

Aortic arch baroreceptor - vagus nerve
Carotid sinus baroreceptor - glossopharyngeal nerve
Both release Ach and decrease blood pressure

Question 19

How is BP controlled long term?

Answer 19

Renin-angiotensin-aldosterone system - increase MAP
Anti diuretic factor - ADH, vasopressin - increase MAP
Atrial natriuretic peptise - ANP, BNP - decrease MAP