Circulatory System

• what is a double circulation system ?

  pumps blood around the heart twice (one system is heart to lungs, another is heart to the rest of the body)
• what is the role of the circulatory system?


  to transport oxygen and nutrients to our cells
• where is the oxygen carried ? 


  in the blood
• what are the three blood vessels ?

  artery, vein, capillary
• what is the function of the heart ?

  to pump blood around the body, supplying the cells with oxygen
• how many chambers does the heart consist of ?

  four
• what surrounds the four chambers in the heart


  thick muscular walls
• what is the function of a valve ?

  to prevent back flow of blood
• what is the function of the left ventricle?

  thick muscular walls to pump oxygenated blood around the body
• what is the function of the right ventricle?

  muscular walls to pump deoxygenated blood to the lungs
• what is the function of the coronary arteries? 


  supply the heart with oxygen
• what is the function of the pulmonary artery ? 


  carries deoxygenated blood to the lungs from the heart
• what is the function of the right atria ?


  receives deoxygenated blood from the body
• what is the function of the left atria ? 


  receives oxygenated blood from the lungs
• what is the function of the pulmonary vein ? 


  carries oxygenated blood from the heart to the lungs
• what is the function of the vena cava?


  carries deoxygenated blood from the body to the heart
• what is the function of the aorta ?

  carries oxygenated blood from the heart to the body
• where are the pacemaker cells located in the heart


  right atrium
• What separates the right side of the heart from the left side of the heart ?

  Septum
• Why is the left side of the heart thicker than the right side ? 


  the left side of the heart pumps blood all around the body whereas the right side pumps blood only to the lungs
• Give two ways a health artery is different from a artery affected by coronary heart disease.

  1. Healthy artery has a bigger lumen
  2. Healthy artery has less fatty deposit
• what is the advantage of have more red blood cells?


  more oxygen --> more respiration -->more energy released efficiently
• name two components of the blood other than rbc and wbc

  blood plasma and platelets
• What type of tissue is the wall of the heart made of ?

  cardiac muscle tissue
• name two substances transported in the blood apart from urea ?


  glucose and amino acids
• why is have more rbc an advantage to athletes ?

  MORE oxygen --> MORE respiration --> MORE energy released efficiently
• What conditions may be used to treat an artificial pacemaker ? 


  irregular heart beat/ arrythmia
• Compare the structure of an artery with a vein


  artery has THICK muscular walls and smaller lumen to main blood pressure.

  vein has THINNER muscular walls and larger lumen as the blood is not at pressure, also veins have valves to prevent backflow of blood
• Which two blood vessels carry deoxygenated blood ?


  vena cava and pulmonary artery
• where does the pulmonary artery take the blood to? 


  lungs where it becomes oxygenated
• Why are rbc red ? 


  rbc are red because of the haemoglobin in them
• what is diffusion 


  net, random movement of particles from an area of high concentration to low concentration ; against the concentration gradient
• what is sickle cell anaemia ?

  misshapen rbc --> smaller volume --> can carry less oxygen ---> slower diffusion of oxygen --> less oxygen reaches the cell --> less respiration --> less energy releases
• what are some symptoms of sickle cell anaemia ?


  shortness of breath / tired quickly
• how can coronary heart disease be reduced ? 


  reducing consumption of alcohol/ reduce smoking / reduce high fat and high salt diet / reduce lack of exercise
• what are statins ? 


  tablets/drugs that slow the buildup of fat, so reduce the amount of bad cholesterol
• what are some advantages of statins ? 


  1. reduce risk of heart attacks
  2. increases the amount of good cholesterol (HDL)
• what are some disadvantages of statins ?


  1. Need to take them for a long time
  2. Side effects
• what is a stent ? 


  mesh tube inserted into the artery to open it up
• what is the advantage of a stent ? 


  1. Lowers the risk of heart attack
  2. Long lasting