Cellular Energy Production: Mitochondria and ATP

Overview of Cellular Structure

• The human body is composed of trillions of cells.
• Each cell requires energy to function.

Role of Mitochondria

• Energy production occurs in the mitochondria.
• Mitochondria converts food into chemical energy, specifically ATP (adenosine triphosphate).
• ATP is released by mitochondria for cellular use.

Mitochondrial Structure

• Consists of two membranes:
  • Outer membrane: Separates mitochondria from the cytosol.
  • Inner membrane: Surrounds the matrix.
• Intermembrane space: Located between the outer and inner membranes.

ATP Production Mechanism: Oxidative Phosphorylation

• Occurs at the inner membrane of mitochondria.
• Involves several membrane protein complexes.
• Nutrients provide high-energy electrons (in the form of NADH).

Process of ATP Production

1. Electron Transport:

   • High-energy electrons are used by protein complexes.
   • Protons are pumped from the matrix to the intermembrane space, creating a proton gradient.
   • This gradient is formed as positively charged protons are attracted to the negatively charged matrix.

2. ATP Synthesis:

   • Protons re-enter the matrix through the ATP synthase protein complex.
   • Their movement catalyzes the production of ATP.