Molecules move and can cross membranes-sometimes!
Channel: S M K
Date: 2022-06-06

Diffusion is the principle that spread molecules out across an area, including the delicious smell of cookies baking; if you smell them from the living room (unless you live in a studio) then the smell has diffused from the kitchen.
Some molecules also cross membranes, but it depends on the size, polarity (or lack thereof) and concentration of the molecule. This video also explores the very neat channels our cells use to move water, called aquaporins (not to be confused with the mini water bottles called "Aquapods" which came out the same semester I first learned about aquaporins...)