Recently had a homework on the cell membrane, i do know that larger molecules that cant fit through the polar heads into the cell (like gases can...and small molecules?!) can get through only if they qualify the shape fitting of the channel protein- the one that reaches all the way from the outside to the inside of the membrane.
hope this helps
Large molecules and ions pass through the cellular membrane via protein channels.
Active transport
During osmosis, water molecules move through the cell membrane by passing through microscopic openings in the membrane. The openings are large enough for the water molecules to pass through.
The polar molecules goes through facillated diffusion. The molecules goes through the channel or membrane protein which then goes inside the cell.
A cell membrane is in every plant and animal and it lets in water, nutrients, and food to the cell. The membrane MUST be permeable because then it wouldn't of let the in water, nutrients, and food into the cell. If the membrane was stiff, the molecules of water, nutrients, and food would not be able to fit into the cell.
The molecules that can pass through the cell membrane of the human cell include water. Other molecules include fat soluble vitamins.
The cell membrane (or plasma membrane) shows semi-permeability. In short some substances, such as gases and small electrically-neutral molecules CAN pass, while others like glucose and other large polar molecules CANNOT pass. Although glucose and other large polar molecules cannot pass through the semi-permeable cell membrane, they may enter through the interior of transport proteins.
The membrane is semi-permeable. Sugar molecules are too large to diffuse through.
Phagocytosis
How do small molecules get through a cell membrane
During osmosis, water molecules move through the cell membrane by passing through microscopic openings in the membrane. The openings are large enough for the water molecules to pass through.
The polar molecules goes through facillated diffusion. The molecules goes through the channel or membrane protein which then goes inside the cell.
A cell membrane is in every plant and animal and it lets in water, nutrients, and food to the cell. The membrane MUST be permeable because then it wouldn't of let the in water, nutrients, and food into the cell. If the membrane was stiff, the molecules of water, nutrients, and food would not be able to fit into the cell.
Diffusion or if the molecules are too large they go through the transport proteins.
Molecules can not pass through the cell membrane, because endocytosis is important for those large molecules that can not pass through the cell membrane!!
Some molecules can't go through the cell membrane.
The molecules that can pass through the cell membrane of the human cell include water. Other molecules include fat soluble vitamins.
Through specialized carrier proteins in the cell membrane.
A large molecule that can not enter the cell through myosis enters the cell through by endocytosis. Endocytosis is an example of active transport.