Cellular organelles

Cellular organelles are structures within a cell that carry out a particular function in the cell.

Types of cells

Eukaryotic cells – cells with a membrane bound nucleus and organelles.

Prokaryotic cells-cells without a membrane bound nucleus and organelles.

Types of organelles

Nucleus

The control centre of a eukaryotic cell that is membrane bound, which houses the genetic material of a eukaryotic cell (DNA).

Mitochondrion (Mitochondria = Plural)

The site of cellular respiration in eukaryotic cells that is used to synthesis ATP ( energy currency used in cells).

Ribosomes

Small structures that are not enclosed by an membrane and are composed of rRNA and protein. They are the site of protein synthesis and can be free (found in the cytoplasm) or bound (attached to the endoplasmic reticulum).

Endoplasmic reticulum

The site of transport of molecules within the cell. It can be considered smooth (no ribosomes) or rough (with ribosomes).

Golgi apparatus (or complex or body)

The site of packaging of molecules within the cell into secretory vesicles that can be then discharged by exocytosis.

Lysosomes

Fluid filed sacs that contain digestive enzymes that play a rule in regulated cell death (apoptosis)

Peroxisomes

Contain enzymes that destroy toxic materials such as hydrogen peroxide.

Endosomes

Found in animal cells pass on material to lysosomes for digestion.

Chloropalsts

The site of photosynthesis in plant cells that contain chlorophyll (light trapping pigment in photosynthesis).

Vacuole

A membrane bound sac containing fluid, sugars and ions. Particularly large in plant cells.

Cytoskeleton

Structural components that are used to provide support to the cell. They consist of microfilaments (actin filaments), microtubules and intermediate filaments.

  • Intermediate filaments are involved in giving the cell strength and rigidity.
  • Actin filaments are involved in movement of the cell, modifying cell shape and rearranging organelles in the cell.
  • Microtubules bind motor proteins that are used to transport vesicles around in the cell.

Cell membrane

Acts as a semi permeable barrier that regulates what enters and leaves the cells.

Centriole

A pair of cylindrical structures that made up of several tubes that form spindle during cellular division.

Flagella 

Extension of cell membrane and provides a means of locomotion for the cell (only found in some cells)

Cilia

Hair like projections on the surface on some cells.

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Organelles interact in the export of proteins

Structure Function
Cell membrane It controls the entry of raw materials, such as amino acids, into the cell.
Nucleus The nucleus has coded instructions (ie DNA) for making the protein, that gets copied during transcription.
Ribosome Organelle where the production of the protein occurs (where translation occurs).
mitochondrion Organelle  that provides an energy source (in the form of ATP) to synthesis the protein.
Endoplasmic reticulum Transport channels through which the newly made protein is moved within the cell.
Golgi complex Packages the protein into vesicles for transport across the cell membrane and out of the cell.

  1. http://kids.britannica.com/elementary/art-121301/Cytoplasm-is-contained-within-cells-in-the-space-between-the