[quote][b]Posted by:[/b] flamechu I have to read these two paragraphs then sumerize them in three sentences. I'm not lazy, I just don't get it. Large protein molecules and bacteria may enter a cell when they are surrounded by the cell membrane. The cell membrane folds in on itself, enclosing the item in a sphere. The sphere pinches off, and the resulting vacuole enters the cytoplasm. This process is called [b] endocytosis [/b] (en duh sy TOH sus). Some one-celled organisms, such as amoebas, take in food this way. Vesicles and vacuoles are transport and storage structures in a cell's cytoplasm. They release their contents outside the cell by a process called [b] exocytosis [/b] (ek soh sy TOH sus). Exocytosis happens in the opposite way that endocytosis happens. The membrane of the vesicle or vacuole fuses with the cell's membrane, and the vesicle's or vacuol's contents are released.[/quote] Imagine endocytosis as you picking up a pile of dog crap with a baggie turned inside out and wrapped over your hand. The baggie is the cell membrane and the dog crap is the large protein molecules and bacteria. You encircle the crap and take it in and close the baggie. Exocytosis is just the opposite. I know this isin't a superb analogy, but I hope it helps.