Mitochondria
The number in a cell depends on how much energy a cell needs. E.g.
Cardiac muscle cells ⟶ Need more energy ⟶ Have more mitochondria.
Fat cells ⟶ Need less energy ⟶ Have fewer mitochondria.
Structure
Rod-shaped or oval.
Made up of two membranes: Outer and inner membrane.
Outer Membrane
Smooth.
Covers the organelle.
Inner Membrane
Folded ⟶ forms shelves or tubules called cristae.
Contains oxidative enzymes.
Folding of the membrane increases its surface area ⟶ more enzymes can be accommodated.
Matrix inside the inner membrane contains more enzymes for energy metabolism.
Mitochondrial Genome
Circular DNA strands.
Encode some of the mitochondrial proteins.
Function
Powerhouse of the cell
Extract energy from different nutrients
↓
Converts it into ATP
↓
Used as an energy sources for various reactions.
About 95% of total ATPs used by cells are produced in mitochondria.
Other Functions
A reservoir of Intracellular Calcium.
Participate in Apoptosis.