1. CELL THEORY: All cells come from pre-existing cells, Al organisms are composed of cells, and the cell is the basic unit of structure and organisation.
2. MRS GREND: movement, respiration, sensitivity, growth, reproduction, excretion, nutrition and DNA.
3. Prokaryotes
3.1. Capsule: made of polysaccharides
3.2. Cell wall
3.3. Plasma membrane: controls what goes in and comes out of the cell
3.4. Ribosomes: Synthesises proteins
3.5. plasmids: smaller pieces of DNA
3.6. Cytosol: Fliud that everything floats in
4. SA:V- As the volume of a cell increases, the nutriona needs of a cell increases faster that a cell's capacity to satisfy them
4.1. Folds in cells help to increase surface area
4.2. higher SA:V ratio means better diffusion
5. Organelles:
5.1. Ribosomes: Site of protein synthesis, using genetic code from DNA
5.2. Nucleus: Holds DNA, genetic material used for coding proteins, Nucleolus which makes ribosomes
5.3. Mitochondria: Carries out cellular respiration, uses glucose to make ATP
5.4. Endoplasmic reticulum: acts as a highway for proteins, ribosomes are attached and proteins are made here
5.5. Golgi apparatus: Packages and exports substances via vesicles out of the cell
5.6. Lysosome: Digestive enzymes that breakdown cell parts that are not functioning
5.7. Peroxisome: Breaksdown substances that are toxic to the cell
5.8. Cytoskeleton: aids in giving structure to the cell and holds organelles in place
5.9. Centriole: plays a role in cell division to split the DNA apart
5.10. Chloroplasts: Found in plant cells that converts light energy into glucose
5.11. Vacuole: Storage unit for materials in the cell and disposes off of waste
5.12. Cell: support anr rigidity to the cell
5.13. Vesicle: Used for transporting materials around the cell
5.14. Cilia: beat in a wavelike motion that help a cell move or create water currents to help the uptake of nutrients
5.15. Flagella: long strand helping in motion of the cell
6. Cellular respiration: glucose + oxygen --> carbon dioxide + water
7. Eukaryotes
7.1. Nucleus: Containing DNA
7.2. Ribosomes: Synthesising proteins
7.3. Golgi Apparatus: Processing and packaging center within a cell
7.4. Endoplasmic Reticulum: Producing proteins and lipids and transporting them through the cell
7.5. Plasma membrane: Controls what goes in and comes out of the cell
7.6. Mitochondria: the site of celular respiration, where energy is made
7.7. Cytoplpasm: fluid that holds organelles in place
7.8. Lysosome: Digestive enzymes that work to destroy old cell parts etc
8. The fluid mosaic model
8.1. Phospholipid bilayer, hydrophobic lipid tails and hydrophillic phosphate heads, and proteins embedded into the layer, giving the name mosaic
8.2. Lipid tails: made of fat and hydrophobic "water-fearing" non-polar
8.3. Phosphate head: Polar, hydrophilic and water-loving
8.4. Integral proteins: embedded into the bilayer and span the width of the bilayer, reaching from one side to the other, called trans-membrane proteins
8.5. Peripheral proteins: Anchored to the exterior of the plasma membrane
8.6. Glycolipids: sugar chain stuck to the lipid bilayer
8.7. Glycoproteins: Sugar chain stuck to the proteins on the plasma membrane
8.8. Cholesterol: Lipid that ensures fluidity in the plasma membrane
8.9. Carbohydrates: Some hospholipids and proteins have chains of carbohydrates attached to them called glycolipids and glycoproteins
8.9.1. Glycolipids: Cell identity, indentifying as 'self'
8.9.2. Glycoproteins: Cell identity, intracellular joinings and anchorage
9. Active boundary, some substances are transported between cells, message and signals are recieved
10. Transport across the plasma membrane
10.1. Does not require energy
10.1.1. Simple diffusion
10.1.1.1. Movement of solutes from a high to low concentration, DOWN a concentration gradient
10.1.2. Facilitated Diffusion
10.1.2.1. Protein mediated transport, from a high to low concentration, for substances that cannot simply diffuse like charged ions
10.1.2.1.1. Channel proteins: A central narrow, water filled pore which creates a hydrophilic passage for charged ions and small polar particles
10.1.2.1.2. Carrier proteins: Binds to a cargo molecule, and changes shape to deliver onto the other side of the other side of the plasma membrane, important for large, uncharged substances such as glucose
10.1.3. Osmosis
10.1.3.1. The net movement of water through a semi permeable membrane from a low to high concentration of solvent
10.1.3.1.1. isotonic: Equal concentration inside and outside of the cell, equal net movement of water
10.1.3.1.2. hypertonic: more solute IN the cell, water flows into the cell and cell expands
10.1.3.1.3. hypotonic: more solute OUT of the cell, water flows out of the cell and cell shrinks
10.2. Does require energy
10.2.1. Active transport
10.2.1.1. the movement of substances from a low to high concentration, AGAINST the concentration gradient, requiring ATP.
10.2.1.1.1. Protein pumps which use enzymes to catalyse a reaction which powers active transport to move a substance across the membrane
10.2.2. Bulk transport
10.2.2.1. Endocytosis- the bulk transport of material into a cell.
10.2.2.1.1. Phagocytosis:Part of the plasma membrane encloses around the food material and pinches off to form a vesicle which is then used as a form of transport into the cell, a phaogocytic vesicle, FOR AMOEBAS
10.2.2.2. Pinocytosis: used by eukaryotic cells, transport of material in solution/liquid form
11. Crossing the plasma membrane
11.1. Hydrophilic: water loving and dissolve in water - lipophobic, unable to pass through thr layer
11.1.1. Examples: charged polar moelcules, ions, glucose (because its big) large uncharged polar molecules
11.2. Hydrophobic: Dissolves in lipids, water fearing - lipophilic
11.2.1. Despite water being a polar molecule, it can pass through the plasma membrane due to its small size, the lipid tails move just enough for the water molecule to pass through without being repelled.
11.2.1.1. Examples: Small uncharged polar molecules, gases, ethanol
11.3. Non polar molecues/ uncharged molecues are lipophilic
11.4. Polar molecues dissolve in water and are therefore lipophobic and hydrophilic
12. The Roles of proteins:
12.1. Transport: Facilitating the movement of substances across the bilayer
12.1.1. for example, channel proteins facilitate the transport of small, charged ions, or carrier proteins move larger molecules through the bilayer against the concentration gradient