pressure

[blackeyed]

Is pressure is a kind of energy?

[Count-A-Strong]

http://hyperphysics.p....edu/hbase/press.html

[jomifl]

assuming you are referring to the pressure of fluids, pressure is a measure of the number of molcules, their mass and their temperature. It is indirectly related to the heat energy in the fluid so in that sense it is a kind of energy. however strictly speaking it is a force.

[vascop]

So the answer to your question is No. It is force per unit area. eg
pounds per square inch.

[blackeyed]

hmmm.. alright
so i was studying active transport so it would mean now that pressure wont account for energy in this case

[jomifl]

My previous answer only really applies to gases, liquids are another matter.

[vascop]

If pressure is acting on something and that something moves then energy is being expended. Is that what happens in active transport?

[jomifl]

By acvtive transport do you mean transport of ions across cell membranes?

[New Judge]

Pressure is a manifestation of energy rather than energy itself.

If you heat water in a boiler and generate steam the pressure of the gases in the boiler goes up as a result of the energy (the heat) being applied to it. A bicycle pump gets hot with use as a result of the compression of the air within it, the compression being supplied by the user’s arm.

I don’t know much about “active transport” but I believe it relies on chemical energy rather than pressure to transport substances across cell boundaries.

[blackeyed]

active transport is a process that takes place in plants and by definition its a process in which a substance moves across a membrane from a region of its lower concentration to a region of its higher concentration against a concentration gradient, using energy.
The energy for this is provided by the ATPs in the cell, but i was wondering if pressure can also provide this energy?

[New Judge]

If it can the pressure would have to be provided by some form of energy.

[vascop]

If you think of pressure created by steam inside a vessel, then assuming no loss through the walls of the vessel, nothing would change. If you fitted a piston to the vessel and locked it in position and put the steam in again, then everything would be the same as before. If you unlock the piston then the pressure of the steam on the area of the piston would produce force and the piston would move. This is when energy is used up - when a force causes movement. The pressure in the gas would go down to represent the loss of energy,
This is a simplified explanation which assumes that no heat is lost through the walls, but it illustrates the point that the pressurised steam is capable of providing energy to move the piston.
Remember that energy/work is equal to force x distance moved in direction of force

[vascop]

blackeyed - It sounds from your description of AT as though there would be a pressure difference across the membrane - this would create a force on the membrane and things would then move across from the high pressure side to the low pressure side and this would consume energy and the pressure difference would go down as a result.

[blackeyed]

vascop thats what i am asking if something of that is possible or not