Describe effects of tar and carcinogens in smoke on the respiratory system In general tar and carcinogens damage the respiratory system whereas the carbon monoxide and the nicotine damage the cardiovascular system

Tar and how it causes chronic bronchitis (the damage and obstruction of the airways) Tar stimulates the goblet cells to produce excessive mucus It also damages the cilia As a result, the mucus with the bacteria and the pathogens gets accumulated in the bronchioles, obstructing them With time, the damaged epithelium will be replaced with scar tissue and the smooth muscle in the bronchioles gets thicker Which makes it harder to breatheSigns and symptoms of chronic bronchitis Smokers Cough Sputum production Chest pain Sore throat

Emphysema (gradual breakdown of the alveoli, decreasing the surface area for gas exchange) The inflammation of constantly infected lungs causes the phagocytes to line the airways Once there, they release the enzyme elastase (which breaks down elastin in the alveoli walls ) so that they can reach the surface and remove the bacteria With reduced elastin, the alveoli cant recoil and stretch as effectively during ventilation as a result the bronchioles collapse, trapping air in the alveoli which often burst This reduces the surface area for gas exchange, less oxygen is absorbed into the bloodSigns and symptoms of emphysema Faster breathing rate Wheezing BreathlessnessChronic Bronchitis and Emphysema often occur together

Lung cancer Lung cancer will take 20-30 years to develop Tar contains a lot of carcinogens, these react with the DNA in the epithelial cells producing mutations which leads to tumour As the cancer develops, it spreads to the bronchioles and enters the lymphatic system Cells will break away and spread to other organs (metastasis), now we have secondary tumorsIf there are secondary tumors formed throughout the body, surgery to remove these will not help recover the patient.Signs and sympotom s of lung cancer Coughing up blood Chest pain Difficulty to breathe Pneumonia Breathlessness

Effects of nicotine and carbon monoxide on the respiratory systemNicotin e Drug Absorbed readily in the blood Stimulates the nervous sytem to reduce diameter of arterioles Stimulates the releases of adrenaline from the adrenal glands As a result, heart rate and blood pressure increases and there is a decrease of blood supply to the hands and feet Increases the risk of thrombus (blood clotting) Stimulates release of dopamine (which reinforces pleasurable experiences) hence nicotine is very addictive Also effects hormone production, lowers oestrogen Carbon monoxide Combines irreversibly with heamoglobin to form carboxyheamoglobin This causes the haemoglobin not to be fully oxygenated Oxygen transported is 5-10% less in smokers, which increases heart rate Tobacco smokes contribute to atherosclerosis Atherosclerosis is accumulation of fatty materials, dead tissues (atheroma) The atheromatous streaks in a normal artery can start at any time from childhood They start as a result of damage to the lining by tobacco smoke or high blood pressure In response to this, phagocytes stimulate the gowth of smooth muscle cells and cholesterol the cholesterol-rich atheroma forms plaques which becomes rough, hardened and making the arteries less elastic and restricitn blood flow as the plaques enlarges , it causes the lumen to narrow reducing blood flow and increasing heart rate the plaque may break through the artery lining giving it a rough surface, the blood will no longer flow smoothly, causing it to form thrombus (blood clot) the thrombosis affects the blood flow even more, causing the tissue to starve of nutrient, oxygen if this happens in a coronary artery, heart muscle dies, heart attack (myocardial infarction) if this happens in the brain, its a stroke

Stroke when an artery in the brain bursts, blood leaks into brain tissue (brain haemorrhage) or when an artery in the brain is blocked because of atherosclerosis the brain tissue straves and dies (cerebral infarction) because of stroke,people will tend to lose their ability to speak or memeory , personalities can change, paralysis add image

4scoronary heart disease 2 arteries branch from the aorta to supply the muscles of atria and ventricles of the heart CHD is the disease of these two arteries With atherosclerosis, the heart has to work a lot harder to supply oxygen during exercise the main cause of CHD is atherosclerosis (reduced blood supply to the heart)

three forms of CHD

Angina Pectoris less severe sympotom of CHD Its main symptom is chest pain, the pain starts whilst exercising, and disappears when resting, the pain is caused by severe shortage of blood to the heart muscle however the heart muscle downs not die MYOCARDIAL INFARCTION- heart attack , when a moderately large branch of the coronary artery is obstructed, the heart muscles starves and dies, this casues a servere and sudden pain which is the heart attack Heart failure blockage of a main coronary artery hence the heart gradually weakens and stops pumping efficiently