• Organelles are structures that carry out different functions within a cell.
  • Organelles in a cell are analogous to the organs in a body.
  • Organelles are suspended in a water-based fluid called cytosol.

The Nucleus

  • The nucleus stores the genetic information (chromosomes) of eukaryotic cells.
  • The nucleus is roughly spherical and is surrounded by two membranes.
  • The nucleus is the ‘brain’ of a cell.

The Mitochondrion

  • Mitochondria are the power houses of a cell.
  • Mitochondria convert biomolecules (i.e. fats and sugars) into energy.
  • By-products of energy production in mitochondria may damage DNA and cause mutations.

The Ribosome

  • Ribosomes are made up of two large complexes comprised of RNA and protein.
  • Ribosomes are located in the cytosol. Their function is to read RNA and produce proteins in a process known astranslation.

The Cytoskeleton

  • The cytoskeleton is an intricate network of proteins that criss-cross the cytoplasm of a cell.
  • Actin and tubulin are the proteins used to build main fibers of the cytoskeleton (microfilaments and microtubules, respectively).
  • The cytoskeleton serves several key functions:
    • Provides structure to cells and a place to anchor organelles
    • Cell motility
    • Control of cell division during mitosis
  • Changes in the cytoskeleton that allow increased movement are observed in cancer cells.
  • Many anti-cancer drugs work by interfering with the activity of cytoskeletal proteins.