small size - each of the alveoli is a small sphere about 300 μm in diameter, giving it a larger surface area to volume ratio than larger structures number - there are around 700 million alveoli ...

The cells in the body need oxygen to release energy from food efficiently by carrying out aerobic respiration. A waste product of aerobic respiration is carbon dioxide. The layer of moisture in ...

Diseases that can affect these airways include: Your airways branch into tiny tubes (bronchioles) that end in clusters of air sacs called alveoli ... on your lung's surface slide along the ...

As you exhale, your alveoli shrink and force carbon dioxide out of your body. The damage caused by emphysema makes your lungs’ overall surface area shrink, and it makes it hard to get fresh air ...