The very function, or job of CELL MEMBRANES is to protect the cell from it's surroundings, or in other words, to keep it safe. It controls the movement of substances in and out of cells and organelles, like a guard watching for suspicious activity and protecting something.
The cell membrane itself is a thin, flexible layer around the cells of all living things. It separates the inside of the cells from the outside of the cells.
Answer:
1. The animal can't see what happening behind its head.
2. Head can be moved upto 180 degree angle in most of the animals including humans. But it is not true in case of birds.
Explanation: