heart

• right ventricle pumps deoxygenated blood to lungs
• pulmonary artery carries deoxygenated blood
• left ventricle pumps oxygenated blood around the body
• pacemaker = heart rate controlled by a group of cells in right atrium
• valves - make sure blood doesnt flow backwards

  blood is at low pressure
• coronary heart disease:

  restricts blood flow

  less oxygen reaches heart

  cells cant respire
• stents - tubes inserted inside arteries to keep them open so blood can pass through

  ADV: lower heart attack risk

  effective for long time

  quick recovery time

  DIS: risk of infection

  develop blood clot -> thrombosis
• statins - reduce cholesterol level in blood, causes fatty deposits to form inside arteries

  ADV: reduce risk of strokes and heart attacks

  can prevent other diseases

  DIS: side effects

  effect isnt instant

  long term drug - can forget to take them
• benign - non cancerous, tumour grows till no room left

  made of abnormal cells
• malignant - cancerous, tumour grows and spreads to tissues

  grows faster

  made of abnormal cells