HELP!!! Affect of temperature on Cell membrane!!!Watch
sorry have to hand in an essay tomorrow and can't seem to find anything about this.
and say I don't have a clue
our teacher mentioned it in passing. I suppose it could have something to do with the heat giving more energy to all the particles which in turn increases the number of collesions which makes everything go faster
the biggie is really just effect of temperature on proteins - channel and carrier. altering the structure which could allow for bigger or non-specific molecules to pass through or prevent complimentary proteins and substrates binding which means certain molecules which would normally be carried into the cell may not be.
Hmm... I sort of got the impression that as the temperature increased the phospholipid molecules moved round more and so left gaps between them where large substances could pass through. This is why cholesterol is more abundant in the cell membranes of organisms aadapted to hot climates - because it provides stability to the membrane and so stops this happening.
Can someone tell me the Affect of temperature on Cell membrane please, ?
Intrinsic proteins (which allow certain chemicals through like glucose in facilitated diffusion).
Extrinsic proteins (Which are used for cell reception).
Glycolipids and Glycoproteins (Collectively called Glycocalyx, they are used for cell identification and in some cases such as your gut wall, for protection).
Cholesterol (which insures that the cell membrane is not too fluid or too permeable).
If you noticed, the molecules mentioned here are made up of:
and are also selectively permeable.
With temperature increase this means:
Proteins in the membrane change shape, and can eventually denature if the temperature is too hot - a bit like the albumen in your egg turning white in a frying pan. This means a few molecules can no longer can pass though other (mostly harmful) chemicals can pass though as intrinsic proteins change their shape.
Lipids in the membrane, like cooking oil in the a pan, becomes more fluid when temperature increases. The membrane can become too fluid and essentially, break apart if the membrane reaches too high a temperature.
A bit like water and a teabag, when you increase temperature, diffusion occurs faster and molecules that are insoluble become soluble: which is not always a good thing as harmful substances can pass through the membrane more easily.
With temperature decrease this means:
Lipids, olive olive oil in a fridge, becomes more viscous. If it becomes too cold this will cause the phosphilpids in the membrane to become too stiff, preventing growth and movement.
If you try putting cold water on a teabag, not much happens. The same is with the phosphilipid membrane. This can cause some problems: important molecules such as oxygen and glucose, and hormones such as steroids do not diffuse through the cell properly and carbon dioxide out of the cell does not diffuse out of the cell properly.
In extreme cases cytoplasm can freeze and pierce the membrane - the cause of why freezing your red pepper turns it to mush.
Hopefully this helps: It really helps to remember stuff using examples in everyday life.