1. Which of the following is required for active transport to occur across a cell membrane?  * A. 
a concentration gradient
* B. 
a storage vacuole
* C. 
energy
* D. 
water

It’s C- energy because it’s needed in order to transport the cells

Cell division is important to single celled organisms because it allows the cells to reproduce. through cell division, cells make exact copies of themselves. when single celled organisms go through cell division, they make exact copies of themselves which is how they reproduce.