Cardiovascular

Question 1

major 3 components of cardiovascular system:

Answer 1

• Blood
• heart
• blood vessels

Question 2

Arteries

Answer 2

Carry blood away from heart

Question 3

Veins

Answer 3

Carry blood toward heart

Question 4

Arterioles

Answer 4

Control blood blow

Question 5

Capillaries

Answer 5

nutrient and gas exchange

Question 6

Atrial diastole

Answer 6

resting phase where atria fill with blood

Question 7

atrial systole

Answer 7

atria contract and force blood into ventricles

Question 8

What are the Lub dub sounds?

Answer 8

Lub- closure of AV valves/beginning of ventricular systole

Dub- start of ventricular contraction/semilunar valves closing/diastole

Question 9

cardiac muscle:

Answer 9

• involuntary
• striated
• electrical signals allow cell to work as one

Question 10

pacemaker cells

Answer 10

• undergo spontaneous depolarisation which conducts the heart muscles automatically by stimulating AP’s
• never at rest due to a constant leaking of ions

Question 11

Action potential of pacemaker cells and their values?

Answer 11

No resting membrane potential

Na+ and Ca+ influx= +20mv

Question 11

Action potential of pacemaker cells and their values?

Answer 11

Resting membrane potential= -100mv
Na+ influx= +20mv
Calcium influx= =10mv

Question 12

What are the 3 waves in an electrocardiogram?

Answer 12

• p wave
• QRS complex
• T wave

Question 13

What is a p wave?

Answer 13

small upward deflection caused by the depolarisation of the atria during atrial systole

Question 13

QRS complex:

Answer 13

ventricular depolarisation

Question 14

T wave:

Answer 14

small upward defection caused by ventricular depolarisation, and ventricular relaxation

Question 15

Tachycardia

Answer 15

High heart rate over 100BPM

Question 16

Bradycardia

Answer 16

Low heart rate below 60 BPM

Question 17

What does noradrenaline do to the heart?

Answer 17

increases the HR by acting through B1 adrenoreceptors in the SA node in response to stress, exercise, or excitement causing faster depolarisation

Question 18

how does acetylcholine work on the heart?

Answer 18

works through the vagus nerve innovating the SA node, targeting the muscarinic cholinergic receptor, effecting the funny channels; slowing down the time it takes for AP to begin, slowing down HR

Question 19

What control centre of the brain effects HR?

Answer 19

medulla oblonga

Question 20

Mechanical events of cardiac cycle: (5)

Answer 20

1. Late diastole
2. Atrial systole
3. Isovolumic ventricular contraction
4. Ventricular ejection
5. Isovolumic ventricular relaxation

Question 21

What is end diastolic volume?

Answer 21

• 130ml

* Volume of blood in the ventricles at the end of diastole when there are equal volumes in both sides of the heart

Question 22

Blood pressure:

Answer 22

• driving force for blood flow through brachial artery