Deserts, savannas, and grasslands.
hope this helps
I do think that they close to not allow too much of either water or air from entering.
the hollow tube allows water to flow easily.
https://www.bbc.co.uk/bitesize/guides/z28g7p3/revision/1
<span>polar heads outside the cell
non polar head inside the cell</span>
This model suggests that the cell membrane is a dynamic structure, because the proteins and phospholipids move laterally within the lipid bilayer ( so it is more of a fluid than solid)
(Mark me the brainliest if this has helped)