"Hey Potato, I have a BIG science test on Cell Division, Cell Chemistry, and Cell Transport tomorrow," says Broccoli. "I'm super scared!!!"

"Yikes, that is a lot of things to study, so let's get started!" says Potato.

"So first up, let's do Cell Transport," says Potato. "So what is diffusion?" "Diffusion is water," says Broccoli. "Close, but it is molecules moving from high to low concentration - like food coloring moving in water," explains Potato. "It helps move good things into the cells and waste out."

"Oh, I totally get that." "Good." "Next question -- what is osmosis?" "Osmosis is a process...," says Broccoli.

"It is a process but it actually is the diffusion of water across a membrane. Picture water going into a teabag," says Potato. "It helps balance cell fluid levels and nutrients."

"Yeah I knew that. I was just testing your knowledge." "Sure you were," says Potato.

"So next question... what is exocytosis?" "Ex... like Exit....hmmmm. Exocytosis is when large molecules and waste exit the cell and it helps cells communicate." "Wow, your right," says Potato. "YES!!" Broccoli exclaims.

"So next question... what is endocytosis?" asks Potato. "Hmmm... en or enter....Endocytosis is when large molecules enter the cell when cells absorb and engulf them with the membrane. It helps important things get in!" Broccoli answers. "Wow, you are right again!" Potato said."Easy peasy," says Broccoli smiling.

(Cell man enters the room!) "Hello Broccoli and Potato. I heard that Broccoli has a test on cells," "so I am here to help." "Yes I need help he has to study a lot," says Potato yawning. "So what would you like to study now?"