Respiratory SystemGas exchange

Taken from:www.wou.edu

• Why do we breathe?

Terminology!

• Cellular respiration is the aerobic breakdown of glucose in the mitochondria to make ATP.

• Respiratory systems are the organs in animals that exchange gases with the environment.

• “Respiration” is an everyday term that is often used to mean “breathing.”

Respiratory system function

Respiratory systems allow animals to move oxygen (needed for cellular respiration) into body tissues and remove carbon dioxide (waste product of cellular respiration) from cells.

Respiration by Diffusion

• In some animals gases diffuse through their skins.

• These animals have a low metabolic rate.

Specialized structures• gills (aquatic

animals)

• spiracles (terrestrial insects)

• lungs (most terrestrial vertebrates)

Parts of the respiratory system include:

• Nasal cavity• Pharynx• Larynx• Trachea• Bronchi• Bronchioles• Alveoli

Alveoli

The alveoli are moist, thin-walled pockets which are the site of gas exchange.

Gas exchange

Takes place due to concentration gradients: differences of concentration of O2 and CO2 between the alveoli and the capillary.

http://bodysystems-rlj00.blogspot.com/

How do O2 and CO2 move?

http://www.toltec.biz/how_hemodialysis_work

s.htm

Oxygen transport

• Hemoglobin binds to oxygen that diffuses into the blood stream.

Carbon dioxide transport

• Carbon dioxide can dissolve in plasma, and about 70% forms bicarbonate ions.