Plant and Animal Cells
Nucleus; contains genetic material, controls activities of the cell
Cytoplasm; where chemical reactions take place. Contains Enzymes
Cell Membrane; holds cell together controlling what goes in and out.
Mitochondria; where most reactions for respiration take place. Resperation releases energy
Ribosones; where proteins are made in the cell.
PLant Cells; contain most of the above and the few below;
Cell Wall; made of cellulose
Permanant Vacuole; contains cell sap
Chloroplasts, where photosynthesis takes place, and also contain chlorophyll
Yeast and Bacterial Cell
Yeast is a microorganism. A yeast cell has a NUCLEUS, CYTOPLASM, CELL MEMBRANE AND IS SURROUNDED BY A CELL WALL
they have food pockets
Bacterial Cells do not have a nucleus.
A bacterial cell has a cytoplasm and a cell membrane surrounded by a cell wall
The genetic Matherial floats in the cytoplasm because the cells dont have a nucleus
Contain 2 types of DNA; Plasmid and
'Diffusion is the spreading out of particals from an area of HIGH CONCERNTRATION to an area of LOW CONCERNTRATION
- is when oxygen is taken into the cell
- Gradual movement of particles from crowed places to more open places meaning they can move around more freely.
- natural tendancy for stuff to spread out
- Happens in solutions and gasses (particles can move around freely&easily)
- The bigger the difference in concerntration the faster the diffusion rate!!
- the concerntation of oxygen inside a cell is kept low because the cell usues it up gradually.
1) Palisade (Leaf) Cells
- Packed with Chloroplasts for photosynthesising
- Tall shape- large surface area-absorbs alot of carbon dioxide
- Thin shape-pack loads into top and bottom of leaf.
- Where most photosynthesis happens
2) Guard Cells (adapted to open and close pores)
- Special kidney shape-open/close pores in a leaf
- When plant has lots of water they fill with it and go plump and turgid. Makes the stomata open so gasses can exchange for photosynthesis.
- When plant is short of water, the guard cells loose water and become flaccid, making stomata close- stops too much water vapour escaping.
- Thin outter walls and thickened inner walls make opening and closing work
- They are sensetive to light and close at night
- Guard cells adapt to their function of allowing gas exchange and controlling water loss within a leaf.
Specialized Cells.. (2)
3) Red Blood Cells
- concave disc shape gives large surface area for absorbing oxygen.
- Packed with haemoglobin- the pigment that absorbs oxygen
- They have no nucleus- more room for haemoglobin
- VERY IMPORTANT PART OF THE BLOOD
4) Sperm &Egg Cells-Soecialised for REPRODUCTION
- Egg cells-Carry female DNA and to nourish developing embryo in the early stages- contains huge food reserves to feed embryo.
- When Sperm fuses with Egg, the eggs membrane instantly changes its structure to stop anymore sperm getting in. Makes sure the offspring ends up with the right amount of DNA.
- sperm gets male DNA to the female DNA, it has a long tail and a streamlined head to make it swim to the egg.
- Sperms contain alot of MITROCHONDRIA in the cell to provide the energy needed.
- Sperm also carries enzymes in the head to digest through the egg cell membrane.