Anatomy of the heart

Question 1

Heart Coverings

Answer 1

FIBROUS PERICARDIUM
- protection
- anchor
- prevention of overfilling

SEROUS PERICARDIUM
- parietal layer
- visceral layer of epicardium

MYOCARDIUM
ENDOCARDIUM

Question 2

Heart Chambers

Answer 2

• right atrium
• left atrium
• left ventricle
• right ventricle
• interatrial septum
• interventricular septum
• sulcus

Question 3

Heart Valves

Answer 3

Atrioventricular valves
- tricuspid valve
- bicuspid valve

Semilunar valves
- aortic valve
- pulmonary valve

Question 4

Coronary Circulation

Answer 4

Coronary arteries
Coronary veins

Question 5

Pulmonary circulation order

Answer 5

cavae veins - right atrium - right ventricle - pulmonary trunk - lungs

Question 6

Systemic circulation order

Answer 6

pulmonary veins - left atrium - left ventricle - aorta - body

Question 7

Cardiac muscle cells - cardiomyocytes

Answer 7

INTERCALATED DISCS
- desmosomes
- gap junctions

• mitochondria
• myofibrils
  -contractile cells

Question 8

Action Potential - Pacemaker cells

Answer 8

Pacemaker potential - this slows depolarization is due to both opening of the Na+ channels and closing of K+ channels.

Depolarization - the action potential begins when the pacemaker potential reaches threshold. Depolarization is due to Ca2+ influx through Ca2+ channels

Repolarization - is due to Ca2+ channels inactivating and K+ channels opening. This allows K+ efflux, which brings the membrane potential back to its most negative voltage

Question 9

Intrinsic cardiac conduction system

Answer 9

• sinoatrial node = hearts pacemaker
• atrioventricular node - 0.1 seconds delay
• Bundle of his
• Purkinjean fibres
• autonomic nervous system

Question 10

Cardiac cycle

Answer 10

• systole = contraction
• diastole = relaxation
• ventricular filling occurs mid to late diastole ( end diastolic volume EDV )
• ventricular systole = atria in diastole ( isovolumetric contraction phase )
• isovolumetric relaxation = early diastole ( end systolic volume ESV )