Smoking and Disease

HideShow resource information
  • Created by: tiacoles
  • Created on: 18-04-16 17:32

Damage to the cardiovascular system

Artherosclerosis

The hardening of arteries due to formation of fibrous plaques called atheromas in the arterial wall. They contain low density lipoproteins. LDL contains a mixture of protein and cholesterol - how it is transported around the body. 

The formation usually begins when damage occurs to the lining of an artery. This allows LDL to enter and collect. The build up triggers an immune response so white blood cells move to the area. Over time more white blood cells, lipids and connective tissue build up and harden to form a fibrous plaque at the site of damage. This partially blocks the lumen of the artery and restricts blood flow. 

Cigarette smoke contains nicotine and carbon monoxide which causes an increase in blood pressure. This can cause damage to the arteries leading to the formation of atheromas. 

Coronary Heart Disease (CHD)

CHD is when the coronary arteries (supply blood to the heart) have lots of atheromas. This restricts the blood flow to the heart. A reduction in blood flow reduces the amount of oxygen an area of the heart gets and forces the heart muscle to respire anaerobically. This can cause pain (angina) or a heart attack. Smoking increases this because:

  • Carbon monoxide irreversibly combines with haemoglobin, reducing the amount of oxygen transported in the blood. This reduces amount of oxygen available to tissues including the heart.
  • Nicotine makes platelets sticky increasing the chance of blood clots. If clotting happens in the coronary arteries it could cause heart attack. The presence of artheromas also

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Health, illness and disease resources »