Biology AQA 3.1.4 Lung Disease

Infection:When someone becomes infected, their immune system responds by building a wall around they bacteria, this causes hard lumps known as tubercles.The infected tissue then dies and the exchange surface is damaged, so tidal voulme decreases. if this bacteria enters the blood stream, other parts of the body will be infected.

Symptoms:*persistent cough*fever*Lose weight due to decreased appetite

Transmission: Droplet infection-  someone with the disease coughs or sneezes.more wide spread in places of low hygiene and living in cramped conditionsIt can be prevented by a vaccine and treated with antibiotics

Fibrosis is a scar tissue. this can be a result of infection or exposure.Scar tissue is thicker and less elasticThis causes the lungs to be unable to expand and the tidal volume is reducedThis means there is a reduction in the rate of gaseous exchanges, diffusion is slower because of a longer diffusion pathwaySymptoms:shotness of breath, dry cough, fatigue and weakness

Asthma is a respiratory condition where it becomes inflamed from allergic reactionsduring an asthma attack, the muscles produce a lot of muscus blocking up the trachea and bronchi.this causes difficulty when breating.Symptoms: wheezing, light chest and shortness of breath

Emphysema is a lung disease caused by smoking or long term exposure to air pollution.this causes a inflammation and produces an enzyme which breaks down elastin.elastin helps the walls of the lungs to be able to return back to their normal shape.if they cant recoil it means that pressure and tidal volume cant be altered- reducing the rate of gaseous exchange.Symptoms: shortness of breath, wheezing and increased breathing rate

Pulmonary Tuberculosis

The big three