Biology AS Cells

• Found in all living cells.
• Shape varies- mainly a sausage circular shape.
• The site of aerobic respiration.
• They have two phospholipid membranes.
• The outer membrane controls the massage of other materials in and out of the mitochondria.
• Matrix contains enzymes that control the early stages of respiration.
• Cristane provide a larger surface area for the attatchments of enzymes to make ATP, the energy currency of a cell.

• Largest organelle in a cell.
• Contains DNA which has all the information required to make a new copy of the cell and to control it's activities.
• In a dividing cell the DNA molecules are condensed into chromosomes.
• Usually spherical and has a diameter of 10μm.
• Have one or more nucleoli that produce the RNA that is used to make ribosomes.
• Nuclear membrane is a double phospholipid membrane.
• Has large pores to allow large RNA molecules to pass through.

Golgi Apparatus

• Appearance is constantly changing as material moves in and out.
• A group of flattened cavities.
• It takes enzymes and other proteins that have been synthesised in the ER and packages them into the membrane-bound vesicle.
• Vesicles transport materials to other parts of the body.

Lysosomes

• Vesicles that contain digestive enzymes.
• They can destroy old or surplus organelles inside a cell, or they can be used to break down material that has been take to the cell.
• This can be used to break down excessive muscle tissue after birth.

Rough endoplasmic reticulum

• A series of thin intricate channels with ribosomes attached.
• It exsits in the space created by the folds in the phospholipid membrane.
• Narrow fluid-filled space between these membranes acts as a transport system to move materials through the cell.
• Ribosomes carry out protein synthesis. 
• Ribosomes attached to the ER produce proteins destined for export from the cell to be used elsewhere.

Smooth endoplasmic reticulum

• The network of smooth endoplasmic reticulum allows increased surface area for the action or storage of key enzymes and the products of these enzymes.