They must either be lipid soluble (e.g. steroids) or very small (e.g. ions).
permeability
The feature of a membrane that determines whether molecules can cross is its selective permeability. This characteristic arises from the lipid bilayer structure, which allows certain small, nonpolar molecules to pass through freely while restricting larger, polar, or charged molecules. Additionally, specific transport proteins facilitate the movement of these restricted molecules across the membrane, either passively or actively. Thus, the composition and arrangement of the membrane's components play a crucial role in regulating molecular transport.
The speed doesn't necessarily determine the permeability, but the size does. Smaller molecules such as O2 can easily enter the cell while CO2 leaves the cell. There are other criteria that also determines whether a molecule can pass through the plasma membrane such as its solubility. Fat soluble molecules such as steroids can easily pass through the membrane.
A key factor that determines whether a molecule can cross a cell membrane is its size and polarity. Small, nonpolar molecules, like oxygen and carbon dioxide, can easily diffuse through the lipid bilayer, while larger or polar molecules often require specific transport proteins or channels to facilitate their passage. Additionally, the concentration gradient and the presence of membrane proteins can also influence a molecule's ability to cross the membrane.
A key factor that determines whether a molecule can cross a cell membrane is its size and polarity. Small, nonpolar molecules, such as oxygen and carbon dioxide, can easily pass through the lipid bilayer, while larger or polar molecules often require specific transport proteins to facilitate their movement. Additionally, the concentration gradient and the presence of channels or carriers also influence a molecule's ability to cross the membrane.
permeabiity
permeability
permeabiity
mass
permeability
Lipid solubility determines if it will diffuse across. The presence of specific protein carrier molecules determines if it will be transported across the membrane.
permeabiity
permeability
The speed doesn't necessarily determine the permeability, but the size does. Smaller molecules such as O2 can easily enter the cell while CO2 leaves the cell. There are other criteria that also determines whether a molecule can pass through the plasma membrane such as its solubility. Fat soluble molecules such as steroids can easily pass through the membrane.
Yes, hydrophilic is a property that determines whether a molecule is polar or nonpolar. Hydrophilic molecules are polar, while hydrophobic molecules are nonpolar.
mass
size/ polarity can be the factors