osmosis and active transport (active transport to stop us starving (the…
osmosis and active transport
2) the water molecules actually pass both ways through the membrane during osmosis this happens because water molecules move about randomly at all times
3)but as there is more molecules one side than the other there is a steady net flow of water into the area with fewer water molecules into stronger sugar solution
1) a partially permeable is one with a small holes in it only small molecules can pass through bigger molecules cant
4) the stronger sugars solution gets more dilute the water acts like its trying to even up to have the same concentration on both sides.
OSMOSIS IS THE MOVEMENT OF WATER MOLECULES ACROSS A PARTIALLY PERMEABLE MEMBRANE FROM A REGION OF A HIGHER WATER CONCENTRATION TO A REGION OF LOWER WATER CONCENTRATION
5) osmosis is a type of diffusion passive movement of water particles from an area of higher water concentration to an area of lower water concentration
3) then you take them out dry them with a paper towel and measure their mass
4)if the cylinders have draw in water by osmosis they'll have increased in mass if water has been drawn out they'll have decreased in mass you can calculate the percentage change in mass then plat a few graphs .
2)you measure the mass of the cylinders then leave one cylinder in each beaker for twenty four hours or so
dependant variable is the chip mass
independent variable is the concentration of the sugar solution
all other variables must be kept the same so its a fair test
cut up a potato into identical cylinders and get some beakers with different sugar slutions in them one should be pure water and the other should be a very concentration sugar solution (eg.1 mol/dm30 then you can have a few others with concentration in between (eg.0.2 mol/dm3 ,0.4 mol/dm3 ,0.6 mol/dm3 ,etc)
errors -o[potato cylinders were not fully dried the excess water would give a higher mass or it would evaporate from th beaker the concentration would change.
root hairs take in minerals and water
3)gives the plant a large surface area for absorbing water and mineral ions from the soil
4)plants need these minerals ions for healthy growth
2)each root branch will have microscopic hairs
5)concentration of minerals is usually higher in the root hairs cells than in the soil around them
1)cells on a plant root grow into hairs which stick into the soil
6)root hair cells cant use diffusion to take up minerals from the soil.
root hairs take in minerals using active transport
3)it allows plants to absorbed minerals from a very dilute solution against a concentration gradient it needs energy from respiration to make it work
2)its called ACTIVE TRANSPORT
4)active transport also happens in humans for example in taking glucose from the gut and from the kidney tubules
1) minerals should move out of the root hairs if they followed the rules of diffusion the cells must use methods to draw them in.
active transport to stop us starving
the glucose can be taken into the bloodstream when it concentration in the blood is already higher than in the gut I can be transported to cells where its used for respiration
5) active transport allows nutrients to be taken into the blood despite the fact that the concentration gradient is the wrong way.
4)same process used in plant roots is used here in active transport
3)this means that the concentration gradient is the wrong way
2)SOMETIMES there's a lower concentration of nutrients in the gut than there is in the blood
1)higher concentration of glucose and amino acids in the gut they diffuse naturally into the blood
active transport is used in the gut when there is a lower concentration of nutrients in the gut but a higher concentration of nutrients in the blood,