God is LifeGod is Life

The Lord God formed the man from the dust of the The Lord God formed the man from the dust of the ground and breathed into his nostrils the breath of ground and breathed into his nostrils the breath of life, and the man became a living being. Genesis 2:7life, and the man became a living being. Genesis 2:7

It is He (God) Himself, who gives life and breath… It is He (God) Himself, who gives life and breath… Acts 17:25Acts 17:25

In Him we live and move and exist, Acts 17:28In Him we live and move and exist, Acts 17:28

God is LifeGod is Life

It is He (God) Himself, who gives life and breath… It is He (God) Himself, who gives life and breath… Acts 17:25Acts 17:25In Him we live and move and exist. Acts 17:28In Him we live and move and exist. Acts 17:28

Air passes from the nostrils directly into the nasal cavity Air passes from the nostrils directly into the nasal cavity where it is, where it is, moistenedmoistened by mucus, by mucus, cleanedcleaned by the nasal hairs by the nasal hairs and cilia and and cilia and warmedwarmed as it passes over the capillaries as it passes over the capillaries within the nasal cavity.within the nasal cavity.

The air passes from the nasal cavity into the pharynxpharynx, or throat, a tube about 13cm long.It then passes into the larynxlarynx, or voice box. The larynx is supported by cartilagecartilage pieces, the largest one being the Adam’s apple. When food is being swallowed, the opening into the larynx (the glottis), is covered by a flap oftissue called the epiglottisepiglottis.

Next air moves into the tracheatrachea, or windpipe. This is about 12 cm long and about 2.5 cm in diameter. It is reinforced with incomplete rings of cartilagecartilage to ensure that the walls cannot collapse and block off the air supply:

Horse shoe shaped rings of cartilage

It’s a bit like the spiralled wire that supports a children's’ play tunnel.

Air moves from the trachea into two bronchibronchi. Each bronchus passes into a lung and branches into smaller and smaller tubes called bronchiolesbronchioles.

The sequence of branching is: Bronchus secondary bronchus bronchiole terminal bronchiole respiratory bronchiole

Each respiratory bronchiole leads into an alveolar ductalveolar duct. Each alveolar duct leads into an alveolar alveolar sacsac.Small pouches, or alveolialveoli, surround each alveolar sac.The linings of these are made of a single layerof thin flattened cellsthin flattened cells.

There are about 300 million alveoli…

That’s about:•One quarter the size of a doubles tennis court.•One fifth of the size of a basketball court.

The alveoli are surrounded by a network of capillaries. Those originating from the pulmonary arterypulmonary artery, carry deoxygenateddeoxygenated bloodWhilst those leaving the alveoli are oxygen rich oxygen rich and empty into the pulmonary pulmonary veinvein.

So, how does this exchange take place?

Alveolar membraneCapillary membrane

The alveolar membraneand capillary membrane form a very thin membrane across which oxygenoxygen andcarbon dioxidecarbon dioxide readily diffusediffuse.

Alveolus Capillary

Diffusion of O2

Diffusion of CO2

Lungs expand

Diaphragmcontracts and moves down

Rib cage movesup and out

High High PressurPressure Aire Air

Lungs compressed

Diaphragm relaxesand moves up

Rib cage movesdown and in

Low Low Pressure Pressure Air Air

INHALATION EXHALATION

Low Low PressuPressure re ZoneZone

High High PressurePressure ZoneZone

http://www.google.com.au/imgres?imgurl=http://static.ddmcdn.com/gif/human-blockhead-nasal-diagram.http://www.google.com.au/imgres?imgurl=http://howshealth.com/wp-content/uploads/2010/09/structures-in-the-nose-throat-anatomyhttp://academic.kellogg.edu/herbrandsonc/bio201_mckinley/Respiratory%20System.htmhttp://training.seer.cancer.gov/anatomy/respiratory/passages/bronchi.htmlhttp://www.google.com.au/imgres?imgurl=http://upload.wikimedia.org/wikipedia/commons/d/db/Alveoli_diagramhttp://www.umm.edu/patiented/articles/normal_lungs_alveoli_000413.htmhttp://www.ebay.com.au