Cell division is essential to:

1. create new cells

2. grow new tissues

3. repair and replacement of damaged cells.

Asexual reproduction

Sexual reproduction

Involves one parent

Involves two parents

The resulting cell is an exact genetic copy of its one parent.

The resulting cell is mixture of genetic combination from both parents.

Diffusion and osmosis are the 2 processes by which cells exchange food, nutrients from their surroundings and excrete their wastes into their surroundings.

Diffusion is the transfer of chemicals from a region of higher concentration to a region of lower concentration across a concentration gradient, until equilibrium is achieved.

Osmosis is the process by which water exchange occurs in a cell across the semipermeable cell membrane.

Cells gain nutrients from their surroundings and excrete their waste to their surroundings by the process of diffusion. This can happen rapidly if the cell size is small according to the theory of surface area to volume ratio. The rate of diffusion decreases with increase in cell size making the cell less efficient. Therefore, instead of increasing in size, with growth, the cells reproduce to grow larger in number and maintain their efficiency.

Wounds heal over time because of the process of growth of new cells. As new cells grow around the wound, the wound becomes smaller in size until it is completely repaired. This growth on cells for repair in living beings is a naturally occurring process and essential for their survival.