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Of the three, water will move easily. The others require help and therefore the use of energy.
Oxygen molecules are small and nonpolar, which allows them to easily pass through the hydrophobic lipid bilayer of the cell membrane via simple diffusion. Glucose molecules, on the other hand, are larger and polar, making it more difficult for them to move through the nonpolar interior of the lipid bilayer. They require specific transport proteins or channels to facilitate their movement across the membrane.
Glucose is virtually the sole energy fuel of brain. Where as, Muscle can derive energy from glucose, fatty acids and ketone bodies; adipose tissue stores and uses triacylglycerols.Glucose transporters in the cell membrane permit the entry of glucose inside the cells.
Small non-polar molecules may pass through a a semipermeable membrane but others require a protein channel.
It is based on the structure of the cell membrane, which has proteins and lipids in it that make some substances impermeable to the membrane, often based on slight electrical charges and sometimes by size of the molecule or other chemical properties. Some substances require an enzyme or hormone to cross the barrier of the cell membrane, such as binding sites on cell membranes that will not allow glucose into the cell unless insulin binds with the sites, which forms a chemical bridge to allow glucose molecules to pass through the cell membrane into the cell. Without the insulin, the cell membrane is impermeable to glucose.
Of the three, water will move easily. The others require help and therefore the use of energy.
Oxygen molecules are small and nonpolar, which allows them to easily pass through the hydrophobic lipid bilayer of the cell membrane via simple diffusion. Glucose molecules, on the other hand, are larger and polar, making it more difficult for them to move through the nonpolar interior of the lipid bilayer. They require specific transport proteins or channels to facilitate their movement across the membrane.
Glucose is virtually the sole energy fuel of brain. Where as, Muscle can derive energy from glucose, fatty acids and ketone bodies; adipose tissue stores and uses triacylglycerols.Glucose transporters in the cell membrane permit the entry of glucose inside the cells.
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.
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 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.
There are two ways that the molecules (i.e: water) move through the membrane: passive transport and active transport. Active transport requires that the cell use energy that it has obtained from food to move the molecules (or larger particles) through the cell membrane. Passive transport does not require such an energy expenditure, and occurs spontaneously.
I do believe that the answer is facilated diffusion.
Hydrophobic molecules are permeable to the cell membrane. Anything that is samll and hydrophobic will pass easily. Larger, hydrophilic molecules require a transport protein to allow permeability.
Small non-polar molecules may pass through a a semipermeable membrane but others require a protein channel.
Ions cannot pass through such as Na+ and K+ - these require membrane proteins. Some larged polar molecules cannot cross either - such as glucose and sucrose - these also require membrane proteins.
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.