The best answer is A. The purpose of the cell wall is to hold the cell in a specific shape, usually rectangular or square. For example, a plant cell's wall keeps it rigid so that the plant can stand up.
If the cell does not have a wall, it can easily change shape to accommodate for things coming in and out of the cell.
Hope this helps!
Well, the food is in the environment. I would like to compare it with how bacteriae feed (however my biology is quite rusty), that is, they engulf their food and they "digest" -- not the proper term, since there are no organs to do real digestion -- it.
Answer:
because the codon reads 3 bases at a time
