Not allowed:
Macro molecules
polar substances
ions
Allowed:
Small nonpolar molecules
Macro molecules
polar substances
ions
Allowed:
Small nonpolar molecules
-
I hope the question is regarding cell membrane
The movement of molecules across the semi permeable membrane depends on the size, shape, charge, chemical properties, solubility in water or lipids etc ( as cell membrane is a phospholipid bi layer)
Small lipid soluble molecules like Oxygen, lipids etc and small uncharged polar molecules like H2O and CO2 can move in and out easily by diffusion.
Moderately sized molecules like glucose and ions like K+, Na+ etc are generally transported through transport proteins on the membrane (intrinsic proteins)
Large molecules like cholesterol are taken in by endocytosis and moved ut by exocytosis
The movement of molecules across the semi permeable membrane depends on the size, shape, charge, chemical properties, solubility in water or lipids etc ( as cell membrane is a phospholipid bi layer)
Small lipid soluble molecules like Oxygen, lipids etc and small uncharged polar molecules like H2O and CO2 can move in and out easily by diffusion.
Moderately sized molecules like glucose and ions like K+, Na+ etc are generally transported through transport proteins on the membrane (intrinsic proteins)
Large molecules like cholesterol are taken in by endocytosis and moved ut by exocytosis