What kind of structures are embedded in the plasma membrane?
Plasma membrane contain proteins embedded between it's phospholipd bilayer. These proteins can be either channel or carrier. These proteins are also known as transport proteins .
Channel proteins form small pores to let the ions or any charged particle(that is unable to cross lipid bilayer) of a suitable size to diffuse freely through them. These are not actually holes or pores formed in plasma membrane but are channels or pathways for the movement of charged particles which don't get their way through lipid bilayer.
Carrier proteins perform the same funtion but these proteins undergo a bit conformational change to let the particles pass through them. However, the original shape is restored after passage of molecules. Carrier proteins can be uniporters, antipoters or sympoters. These proteins primarily assist active transport of materials across plasma membrane(sympoters & antipoters). However, facilitated diffusion is also accomplished by carrier proteins(uniporters).
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