1. The Plasma Membrane
1.1. Channel proteins allow certain Ions to move in and out of the cell.
1.1.1. These change shape as they move susbatances across the membrane. eg. Glucose.
1.2. Intergral Protiens
1.2.1. Asisist Small sized water soluble substances to cross the membrane
1.2.2. Some Intergal Proteins are GLYCOPROTEINS, these together are cell surface markers.
1.2.3. May act as a receptor for substances. e.g. Insulin.
1.3. Is selectively permeable since it all as substances to gases in and out easily.
2. The cytoplasm
2.1. Concsists of cytosol and the organelles.
2.2. Ribsosomes - manafactures proteins in response to messages (MRNA) from the nucleus.
2.3. Mitochondria - Complex organelles.
2.3.1. 2 Layers of membrane
2.3.2. Have there own DNA
2.3.3. Able to reproduce themselves.
2.4. Lysosomes
2.4.1. These spherical membranes organelles are the cells demolition crew.
3. The Nucleus
3.1. Control of the centre of the cells.
3.2. The nucleus evenvlope surrounds it.
3.2.1. The double layer is similar to mitricindria.
3.3. The nucleloli
3.4. The chromatin
3.4.1. Contains 46 chromosomes in none dividing cells the chromosomes unwind to become chromatin (folded up DNA)
3.5. It is round/oval and is usually the most prominent organelle.
3.6. Most cells have a single nucleus - given centred to the cells.
3.7. Repair and regeneration
3.7.1. All tissues are capable of repair, speed of repair carries depending on the tissue.
3.7.2. Tissue regeneration occurs throughout life replacing cells worn away by friction either internally or externally.
4. Passive Process
4.1. These do not consume energy (ATP) and move with concentration gravity.
4.1.1. Diffusion
4.1.2. Osmosis.
5. Active Process
5.1. These use ATP and move against the concentration.
5.1.1. Active Transport
5.1.2. Endocytosis
5.1.3. Exocytosis.