Explanation

Cell growth happens when one cell divides into two new cells through a process called cell division. There are two main types of cell division: mitosis for body cells and meiosis for sex cells. When tissues or organs need to grow, cells divide to make more cells.

Cell growth is not continuous throughout a cell life. Cells go through specific phases called the cell cycle. They grow, copy their DNA, then divide, followed by a resting phase before growing again.

Both internal signals like hormones and external factors like nutrients control cell growth. A cell does increase organelles before division, but this is preparation for division, not growth itself. The actual growth of tissue happens when division creates more cells.