control of the heart

Question 1

how is the heart controlled

Answer 1

Generates and propagates it’s own action potentials, electrical events are exacty the same as skeletal muscles

Question 2

SA node

Answer 2

ability to initiate an action potential spontaneously which triggers the myocardial fibres to contact

Question 3

properties of cardiac muscle

Answer 3

• automaticity generate AP without being stimulated
• excitability respond to impulse
• conductivity transmit electrical current
• contractility shorten + contract in response to Elec stimulation

Question 5

how is the heart affected by ANS

Answer 5

• sympathetic to increase HR conduction and contraction strength
• parasympathetic to decrease HR, AV conduction contractility and excitability.