PLASMA MEMBRANE

• What is the glycocalyx?

  Superficial membrane carbohydrates
• What are the components of glycocalyx?

  Proteoglycans, glycoproteins, glycolipids
• What are proteoglycans?

  Carbohydrates with protein attached
• What are glycoproteins?

  Proteins with carbohydrates attached
• What are glycolipids?

  Lipids with carbohydrates attached
• What are the functions of glycocalyx?

  Cell recognition, binding, lubrication
• What are integral proteins?

  Part of cell membrane, cannot be removed
• What is a characteristic of transmembrane proteins?

  They span the entire cell membrane
• What can integral proteins transport?

  Water or solutes
• What are peripheral proteins?

  Attached to cell membrane surface, removable
• How do peripheral proteins differ from integral proteins?

  Fewer in number and removable
• What functions do peripheral proteins serve?

  Regulatory or enzymatic functions
• What is the thickness of the plasma membrane?

  6–10 nm
• What is the structure of the plasma membrane?

  Phospholipid bilayer with hydrophilic heads
• What do the hydrophilic heads of phospholipids do?

  Face the membrane surface
• What do the hydrophobic tails of phospholipids do?

  Face inward, away from water
• What is one function of the plasma membrane?

  Physical isolation of cytoplasm
• How does the plasma membrane regulate exchange?

  Controls what enters and exits the cell
• Why is the plasma membrane sensitive to the environment?

  It responds to external stimuli
• What provides structural support in the plasma membrane?

  Proteins perform most functions
• What does the lipid bilayer provide?

  Isolation from the external environment
• What are the main functions of the plasma membrane?

  • Physical isolation
  • Regulation of exchange with external environment
  • Sensitivity to environment
  • Structural support
  • Lipid bilayer provides isolation
  • Proteins perform most other functions
• What is the plasma membrane's primary function?

  It is selectively permeable.
• What does the plasma membrane control?

  • Entry of ions and nutrients
  • Elimination of wastes
  • Release of secretions
• What does the plasma membrane regulate regarding ions?

  It controls the entry of ions.
• What does the plasma membrane manage concerning nutrients?

  It controls the entry of nutrients.
• What is one of the waste management functions of the plasma membrane?

  Elimination of wastes.
• What does the plasma membrane do with secretions?

  It releases secretions.