NO, it does not always require a carrier protein!!
Yes, the carrier protien transports the molecule across the cell membrane, do your homework kids, well, Im doing it too I guess.
FALSE!
No. Facilitated diffusion is just diffusion through membrane proteins. But, it is still diffusion and the net movement of molecules is from high to low concentration and therefore does not require added energy. -H. C =)
The answer is that glucose crosses a semi-permiable membrane by the process of facilitated diffusion. It cannot be by osmosis, because osmosis is the moving of only water from a concentration of high to low.
The process by which molecules such as glucose are moved into cells along their concentration gradient with the help of membrane bound carrier proteins is called facilitated diffusion. Facilitated transport is passive and does not directly require chemical energy from ATP.
Facilitated diffusion occurs against the osmotic potential/concentration gradient and requires energy at the expense of the ATP hydrolysis. There are several way in which this diffusion could occur in the cells. The first one being the ion exchangers. The ion exchangers are coupled with ATPase activity and they exchange ion(s) across the membrane. The most classical example of ion exchanger is the Na+/K+ ion exchanger and Ca+ ATPase. Other way of the facilitated diffusion in the ion channel. These could be voltage gated channel that open in response to the change in the membrane potential and the other being ligand gated channel that operate under the effect of ligand binding.
"Passive" mean that it does not require energy, therefore the passive transport of material across the membrane means that it can transport the material (cells or whatever) without the function of energy across the membrane.
no
facilitated diffusion
Passive diffusion occurs when you have unequal concentrations of solutes on either side of a permeable membrane, therefore facilitated diffusion shouldn't require a difference in solute concentration to drive it.
No. Facilitated diffusion is just diffusion through membrane proteins. But, it is still diffusion and the net movement of molecules is from high to low concentration and therefore does not require added energy. -H. C =)
It does not require the use of the cells energy.
no
Simple and facilitated diffusion are a part of passive transport. This refers to the movement of molecules, atoms and ions across the cell membrane. In both of these processes, molecules move from areas of high concentration to areas of lower concentration because equilibrium is trying to be maintained in living organisms. Simple diffusion just happens randomly and without any aides. Facilitated diffusion uses proteins in the cell membrane to guide polar molecules and ions in and out of the membrane (always to areas of lower concentration) and DOES NOT require ENERGY.Only active diffusion requires energy.
Movement across a membrane that does require energy is called active transport.
The answer is that glucose crosses a semi-permiable membrane by the process of facilitated diffusion. It cannot be by osmosis, because osmosis is the moving of only water from a concentration of high to low.
No, there is no ATP used in facilitated diffusion, because it is a form of passive transport. It only differs from normal diffusion in that it uses transport proteins to move larger or more polar molecules across the membrane of the cell.
The process by which molecules such as glucose are moved into cells along their concentration gradient with the help of membrane bound carrier proteins is called facilitated diffusion. Facilitated transport is passive and does not directly require chemical energy from ATP.
Facilitated diffusion occurs against the osmotic potential/concentration gradient and requires energy at the expense of the ATP hydrolysis. There are several way in which this diffusion could occur in the cells. The first one being the ion exchangers. The ion exchangers are coupled with ATPase activity and they exchange ion(s) across the membrane. The most classical example of ion exchanger is the Na+/K+ ion exchanger and Ca+ ATPase. Other way of the facilitated diffusion in the ion channel. These could be voltage gated channel that open in response to the change in the membrane potential and the other being ligand gated channel that operate under the effect of ligand binding.