Why do we yawn?

Why do we yawn? Get rid of CO2 Stretch Stay alert Nervousness Communicate to others to stay alert Cool the brain Neurotransmitters Warning display (Baboons)

Why is yawning contagious? Mirror neurons

Normal alveoli Emphysema Alveoli

Emphysema

condition in which the alveoli deteriorate, causing the lungs to Malfunctions & Diseases of the Respiratory System EMPHYSEMA condition in which the alveoli deteriorate, causing the lungs to lose their elasticity

asthma http://www.youtube.com/watch?v=aGDi5tI5vTk http://www.youtube.com/watch?v=82gn_rDRpHk http://www.youtube.com/watch?v=aGDi5tI5vTk

Malfunctions & Diseases of the Respiratory System asthma severe allergic reaction characterized by the constriction of bronchioles bronchitis inflammation of the lining of the bronchioles

Malfunctions & Diseases of the Respiratory System lung cancer irregular & uncontrolled growth of tumors in the lung tissue

Pneumonia in upper right lung

Malfunctions & Diseases of the Respiratory System Pneumonia condition in which the alveoli become filled with fluid, preventing the exchange of gases

Bird Flu The Next Pandemic? https://www.youtube.com/watch?v=X0WxcahL78Y 25 min

Mycobacterium tuberculosis

Alveoli with tuberculosis Normal Alveoli Alveoli with tuberculosis

tuberculosis http://www.youtube.com/watch?v=d06YPhGup0Q

Infection with bacterium Mycobacterium tuberculosis. mainly affects and damages the lungs, but the bacterium may spread to any other organ system. slowly progressive and chronic if untreated and death may result.

Humans usually acquire infection by breathing in infectious droplets, which have been expelled from the respiratory tract of infected persons.

Some forms are antibiotic resistant. Treatment with antibiotics is available, but must be administered over many months to achieve remission. Some forms are antibiotic resistant.