12.2.5

Mitochondria

Test yourself

Function of Mitochondria

Mitochondria are often called 'energy factories' of a cell because they make adenosine triphosphate (ATP), which is the cell's main energy-carrying molecule.

Illustrative background for Adenosine triphosphate (ATP)Illustrative background for Adenosine triphosphate (ATP) ?? "content

Adenosine triphosphate (ATP)

  • ATP represents the short-term stored energy of the cell.
  • Cellular respiration is the process of making ATP using the chemical energy found in glucose and other nutrients.
    • In mitochondria, this process uses oxygen and produces carbon dioxide as a byproduct.
Illustrative background for Mitochondria in muscle cellsIllustrative background for Mitochondria in muscle cells ?? "content

Mitochondria in muscle cells

  • Muscle cells have very high concentrations of mitochondria producing ATP.
    • This is because muscle cells need a lot of energy in order to keep the body moving, so a lot of cellular respiration happens in these cells.

Structure of Mitochondria

Mitochondria have a specific structure which allows them to perform their functions in cellular respiration.

Illustrative background for Double membraneIllustrative background for Double membrane ?? "content

Double membrane

  • Mitochondria are oval-shaped organelles which have their own ribosomes, DNA and a double membrane.
    • Each membrane is a phospholipid bilayer embedded with proteins.
    • The space between the membranes is called the intermembrane space.
Illustrative background for Inner membraneIllustrative background for Inner membrane ?? "content

Inner membrane

  • The inner membrane contains folds, called cristae, which increase its surface area.
    • This is important because ATP synthesis takes place on the inner membrane.
  • The space inside the inner membrane is called the mitochondrial matrix, which also contains mitochondrial DNA.

Jump to other topics

1Cell Structure

2Biological Molecules

3Enzymes

4Cell Membranes & Transport

5The Mitotic Cell Cycle

6Nucleic Acids & Protein Synthesis

7Transport in Plants

8Transport in Mammals

9Gas Exchange

10Infectious Diseases

11Immunity

12Energy & Respiration (A2 Only)

13Photosynthesis (A2 Only)

14Homeostasis (A2 Only)

15Control & Coordination (A2 Only)

16Inherited Change (A2 Only)

17Selection & Evolution (A2 Only)

18Classification & Conservation (A2 Only)

19Genetic Technology (A2 Only)

Unlock your full potential with Seneca Premium

  • Unlimited access to 10,000+ open-ended exam questions

  • Mini-mock exams based on your study history

  • Unlock 800+ premium courses & e-books

Get started with Seneca Premium