Each alveolus is cup-shaped with very thin walls.
It’s surrounded by networks of blood vessels called capillaries that also have thin walls.
The oxygen you breathe in diffuses through the alveoli and the capillaries into the blood.
The carbon dioxide you breathe out is diffused from the capillaries to the alveoli, up the bronchial tree and out your mouth.
The alveoli are just one cell in thickness, which allows the gas exchange of respiration to take place rapidly.

3 0

2 years ago

What happens when a cold front replaces a warm front

frozen [14]

Answer:

When a cold front overtakes a warm front, it creates what's called an occluded front that forces warm air above a frontal boundary of cooler air masses.

Explanation:

The presence of a cold front means that cold air is advancing and pushing underneath warmer air. This is because the cold air is ‘heavier,’ or denser, than the warm air. Cold air is thus replacing warm air at the surface.

7 0

2 years ago

What happens during G2 phase

Rudiy27

Answer:

Gap 2 (G2): During the gap between DNA synthesis and mitosis, the cell will continue to grow and produce new proteins. At the end of this gap is another control checkpoint (G2 Checkpoint) to determine if the cell can now proceed to enter M (mitosis) and divide.

Explanation:

6 0

3 years ago