The Respiratory System
The network of air tubes spreading out just like the branches and twigs of a tree, form the structure of the lungs. The trachea, or windpipe, divides into two bronchi and these on entering the lungs, divide into bronchioles, alveolar ducts, alveolar sacs and individual alveoli. The right ventricle of the heart pumps deoxygenated blood to the lungs via the pulmonary arteries. At the alveoli, gaseous exchange of oxygen and carbon dioxide takes place between air in the lungs and blood in surrounding capillaries.
Well said :)
Asheyluvs2dance 1 week ago
Who narrates this, Stephen Hawking?
DaynNightUK 3 weeks ago
great
bbjeanlianda 6 months ago
Cool
yozecool 8 months ago
too fast T_T
xskullxkissesx 9 months ago
this is good man.. i liked it keep up the good work...and help us...
penumak 1 year ago
thx
sppankie 2 years ago
rolf..... lol
zaidmuaz25 2 years ago
nycc..!
sober22gurl 3 years ago
whats this for anyways
abercrombielove96 3 years ago