- Created by: Tia-H
- Created on: 04-04-19 18:55
- High to Low concentraton.
- Passive, random movement of particles.
- Rate affected by concentration and temp.
- Semi-permeable membrane.
- Animal cell- burst.
Cell Division - For Growth And Repair
- Mitosis 1) DNA replicates 2) Nucleus divides 3) Cell divides = Identicle cells.
- Chromosomes- X shaped, Made of protein, contain all DNA code.
- Requires energy- Cells have a lot of mitochondria,for mineral absorbtion.e.g gut absorbs sugar. concentartion gradient increases.
Magnification= Image Size / Object size
Parts Of The Microscope:
- Lens - Eyepiece and objective.
- Stage - Where you put the slide.
- Electron - 3D image. Large Magnification. Expensive.
- Resolving Power - Bigger the power, the easier to distinguish between particles.
Stem Cells- Embryos and Adult Stem Cells
- Uses - Insulin, paralysis, blindnes, growing / repairing organs.
- Plants - Reduce extinction, largen, saves costs.
- Ethics - Religion, interfere with reputation.
- Cancer - The embryo cells divide and grow fast.
- Adult cells can be infected with viruses - Theraputic cloning makes embryos form.
- Undiferentiated cell - egg and sperm cell = zygote.
Differentiation - Cell that is specified for functions
- Animal - Adult stem cells replace faulty blood cells.
- plant - Differentiate through entire life (can always change).
- Large Surface Area: Volume Ratio.
- Small intestine.
- Alvioli - Thin and moist, O2 and CO2.
Algae - Cell wall, chloroplasts, like a plant.
Prokaryotes - (Bacteria)- Single celled organism, no nucleus, plasmid ring, flagella, slime capsule.
Eukaryotes - (Animal & plant cells)- Nucleus contains the genetic material (DNA).
Muscle - Store glycogen, proteins, mitochondria.
Sperm - Flagella, acrosome (contains digestive enzymes), mitochondria, streamlined.
Nerves - Lots of connections, axon (carries impulses), transmitter for chemicals.
Root Hair - Large vacuole and surface area, mitochondria.
Xylem - Transports water, chemicals: lignin (make rigid, forms hollow tubes).
Phloem - Food made in photosynthesis, cell wall breaks down.
Osmosis Potato Practical
Investigating the effect of different concentration of sugar solution on plant tissue
- Cut cylinders of potato tissue and measure each mass.
- Place the potato in different concentrations of the sugar solution.
- After 30 minutes, mesure their mass again.
- If the potato changes in mass it has gained or lost water in osmosis. Osmosis is high to low.
- Independent - (Changed) - Concentration of sugar solution.
- Dependent - (Measured) - Change in mass of potato.
- Control - (Stays same) - Temperature, length of time, volume of solution.
Osmosis Potato Practical
Mistakes or errors:
- Potato needs to be left a long time for a significant change in mass.
- Before weighing the potato a second time, it must be blotted on a paper towel to remove excess solution.
Hazards and risks:
- Care must be taken when cutting the cylinders of potato to ruduce risk of cutting yourself.
Osmosis is the diffusion of particles in water from low concentration to a high concentration through a partially permeable membrane.