Definitions on cardiovascular system

• Systolic pressure


  The amount of pressure in your arteries during the contraction of your heart muscle(the top number of the fraction )
• Diastolic pressure


  The pressure when your heart is between beats(the bottom number of the fraction )
• Blood pressure


  A measure of the force that your heart uses to pump blood around your body
• Vasodilation


  Restricts the blood flow to an area
• Vasoconstriction increases blood Flow to an area
• Precapillary Sphincters


  Regulate blood flow into the capillary network by contracting and relaxing
• Muscles are working hard and demand more oxygen + nutrie


  The pre-capillary Sphincters can reduce blood flow to areas like the digestive Sy, allowing more blood, nutrients, oxygen to wo?
• Muscles are working
• Heart Rate


  The number of cardiac cycles per minute (bpm)
• Heart rate


  Rises in direct proportion to exercise
• Stroke Volume


  The amount of blood pumped from the left ventricle per heart beat
• Stroke Volume


  Increases with exercise due to increased venous return
• Cardiac Output


  The volume of blood pumped out of the left side of the heart in one minute determined by the amount of blood pumped from the left ventricle per heartbeat and by number of hbpm
• Cardiac Output


  Determined by the amount of blood pumped from the left ventricle per heart beat and the number of beats per minute
• With exercise what will happen to:

  1. Heart Rate - Increases as more oxygen needs to be pumped around the body

  2.

  Stroke Volume - Increases due to increased venous return, more blood circulating around the body

  3.

  Cardiac Output - Increases as a result of the increases in both heart rate and stroke volume
• Release of adrenaline


  Heart rate rises
• Explanation for heart rate rising due to adrenaline release

  Increase in blood flow