The organelle mitochondria known as the powerhouse of the cell. Process of cellular respiration takes place in mitochondria to generate energy required for various chemical activities in the form of ATP.
This is the reason that mitochondria is known as powerhouse of the cell.
∆ABC is an isosceles triangle in which AB = AC. Side BA is produced to D such that AD = AB (see Fig. 7.34). Show that ∠ BCD is a right angle.

Read More: Fundamental Unit of Life: Cell
The different parts of a cell and their functions are as follows:
