Pretty sure it's D. Mercury
Answer:
There are two major ways that molecules can be moved across a membrane, and ... is trying to be evenly distributed everywhere, like dropping food coloring in water. ... These channels are almost always specific for either a certain molecule or a ... When a molecule moves down its concentration gradient is it participating.
Answer:When present en masse, it is possible to see pollen on surfaces of objects such as cars, patio tables, sidewalks, etc. Pollen on CarHowever, it is rare to actually see pollen when it is present in the air because the number of grains in a given volume of air is too low to be seen with the unaided eye.
Explanation:
The last on it makes copied of itself.