Unit4- 1.4~ Function of heart

Question 1

What are the functions of the heart?

Answer 1

• Double pump
• Diastole
• Systole
• Cardiac cycle
• Role of component parts

Question 2

What is the function of the heart?

Answer 2

• To pump blood throughout the body
• Delivers oxygen and nutrients to the bodys cells and removes waste products
• Does this by contracting and relaxing
• Heart contracts to pump blood then relaxes to refill blood. The right side pumps blood to lungs, picking up oxygen. Left side recieves blood, pumping to body
• Heart must maintain homeostasis, by adjusting blood pressure and volume

Question 3

What is the cardiac cycle?

Answer 3

Referes to a complete heartbeat that includes diastole (Heart is in a state of relaxation and fills with blood), systole (heart chambers contract and pump blood) and the intervening pause.

Question 4

What is diastole?

Answer 4

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

Question 5

What is systole?

Answer 5

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

Question 6

What is the intervening pause?

Answer 6

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

Question 7

What 2 controls is the cardiac cycle regulated by?

Answer 7

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

Question 8

Explain the intrinsic control.

Answer 8

• 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 9

Explain the extrinsic control.

Answer 9

• 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