tructure of Plasma Membrane

 
3.1 Structure of Plasma Membrane
 
We will learn about the structure of plasma membrane,the movement across the plasma membrane,passive and active transport in plasma membrane.
 
  The necessity of movement of substances across a plasma membrane:  
     
 
  • Allow some substances to move into and out of the cells to maintain the living processes.
  • Regulates the movement of substances across the plasma membrane
 
     
The structure of plasma membrane:
 
Source:[Biologi Text Book KSSM Form 4]
 
Types of molecules Description
Cholesterol
  • Strengthened the plasma membrane
  • Makes the plasma membrane to be more flexible but less permeable to water-soluble molecules
Carrier protein
  • Transport large molecules such as glucose, amino acids, and vitamin C across the plasma membrane
Pore protein
  • Allow small and water-soluble molecules such as ions to pass across the plasma membrane through passive transport
Glycolipid
  • A combination of lipids and polysaccharides helps the cell-cell recognition
Glycoprotein
  • A combination of proteins and polysaccharides helps the cell-cell recognition
 
  The permeability of plasma membrane:  
     
 
  • The plasma membrane is semi-permeable because it only allows certain molecules or ions to pass through it by simple diffusion