Health&SocialCare: Unit4- 1.5~ Control and regulation of cardiac cycle

Question 1

What is the cardiac cycle?

Answer 1

Referes to a complete heartbeat that includes diastole, systole and the intervening pause.

Question 2

What is diastole?

Answer 2

The period during which the heart relaxes and the chamber fills with blood

Question 3

What is systole?

Answer 3

The period during which the heart relaxes and the chambers fill with blood

Question 4

What is the intervening pause?

Answer 4

A breif moment of rest that occurs after systole and before diastole phases

Question 5

What 2 controls is the cardiac cycle regulated by?

Answer 5

• Intrinsinc (coming from within the heart)
• Extrinsic (coming from outside the heart

Question 6

Explain the intrinsic control.

Answer 6

• The heart has a pacemaker, the sinoatrial node (SA node), in the right atrium, which initiates each heartbeat and determines heart rate
• Electrical impulses generated by SA is spread across the atria, causing them to contract
• Signal is passed to atrioventicular node (AV node), which acts as an electrical bridge allowing signals to travel from atria to ventricle
• This sequence ensures the right timing for blood flow

Question 7

Explain the extrinsic control.

Answer 7

• Cardiac cycle is also controlled by extrensic factors through the autonomic nervous system (ANS), including sympathetic and parasympathetic nervous system
• Sympathetic nervous system: Speeds up heart rate, increasing force of contraction, preparing body for ‘fight or flight’
• Parasypathtic nervous system: Through vagus nerve, slwos down the heart rate, allowing body to be in ‘rest and digest’ state