Cell Membrane

• What are membranes found in all cells called?

  Cell membranes
• What does the cell surface membrane separate?

  Internal cell environment from external environment
• What are intracellular membranes responsible for?

  Forming compartments within the cell
• What are the three functions of membranes?

  1. Separating different areas
  2. Exchange of substances
  3. Acts as an interface for communication
• What is the structure of cellular membranes primarily made of?

  Phospholipid bilayer
• What components make up a phospholipid?

  Glycerol, phosphate head, two fatty acid tails
• What type of bonds join the components of a phospholipid?

  Ester bonds
• What are the two distinct regions of a phospholipid?

  Polar head and two non-polar tails
• What is the nature of the lipid tail in a phospholipid?

  It is non-polar and hydrophobic
• What is the nature of the phosphate head in a phospholipid?

  It is polar and hydrophilic
• How is the phospholipid bilayer structured?

  Two layers of phospholipids with tails inward
• Why are phospholipids arranged in two layers in the cell surface membrane?

  To protect hydrophobic tails from water
• What is the difference between a phospholipid and a triglyceride?

  Phospholipids have two fatty acids, triglycerides have three
• What are the non-lipid components of the cell membrane?

  • Proteins
  • Cholesterol
  • Glycolipids
  • Glycoproteins
• What is the function of proteins in the cell membrane?

  Involved in cell transport and communication
• What is the difference between intrinsic and extrinsic proteins?

  Intrinsic proteins are embedded; extrinsic are surface-bound
• What is cholesterol's role in the cell membrane?

  Regulates membrane fluidity
• How does cholesterol interact with water due to its hydroxyl group?

  It can form hydrogen bonds with water
• Which molecules are involved in cell recognition and communication?

  Glycolipids and glycoproteins
• What does the term 'fluid mosaic' refer to in the context of the cell membrane?

  • Fluid: Movement of phospholipids
  • Mosaic: Random arrangement of proteins
• What does it mean that the membrane is partially permeable?

  It allows some molecules to pass through
• Which type of molecules can pass through the gaps between phospholipids?

  Small, non-polar molecules
• How do large, polar molecules pass through the membrane?

  Through specialized membrane proteins
• What are the specialized membrane proteins called that assist large, polar molecules?

  Channel proteins and carrier proteins