The heart

Question 1

Where does the heart lie?

Answer 1

Upper part of the thorax, between the sternum and vertebrae

Question 2

How long is the heart?

Answer 2

12cm

Question 3

What is the hearts diameter?

Answer 3

8cm

Question 4

How much does a heart weigh?

Answer 4

250-300g

Question 5

What is the hearts structure?

Answer 5

4 chambers
4 vessels
4 valves

Question 6

What is the tricuspid?

Answer 6

Valve on the right ventricle

Question 7

What is the bicuspid?

Answer 7

Valve on the left ventricle

Question 8

What is the function of valves?

Answer 8

Prevent backflow from ventricular arteries

Question 9

Where are the atrio ventricular valves located?

Answer 9

Within a fibrous ring on the same plane

Question 10

What is cardiac muscle made from?

Answer 10

Short muscle cells or myocytes

Question 11

What are intercalated discs?

Answer 11

Junctions connecting myocytes

Question 12

At what rate does the heart pump blood?

Answer 12

5 litres/min at 70 ml/pump

Question 13

Diastole vs Systole

Answer 13

Expand vs Contract

Question 14

First step to the heart pump

Answer 14

Upper and lower chambers fill, pulmonary and aortic valves are closed

Question 15

Second step to the heart pump

Answer 15

Upper chamber contracts and primes the lower chamber

Question 16

Third step to the heart pump

Answer 16

Lower chamber contracts, AV valves close, blood ejects through the arterial valves which then close

Question 17

What are heart beat rates controlled by?

Answer 17

ANS

Question 18

What’s the role of the pacemaker?

Answer 18

Generate action potentials

Question 19

Equation for cardiac output

Answer 19

Heart Rate x Stroke Volume

Question 20

What is Starling’s Law of the Heart?

Answer 20

The energy released during contractions depends on the initial fibre length

Question 21

What happens to heart rate during exercise?

Answer 21

180bpm at 120-180 ml/beat