Why is a nucleus found in both plant and animal cells?

Because it controls all life activities of the cell

Explanation:

The nucleus has a spherical body which is covered by a double membrane which contains hereditary materials, chromosomes and genes. The functions of the nucleus are as follows:

- it controls all the life activities of the cell

- It stores all the hereditary information as it contains DNA inside chromosomes which take part in cell division.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.