1. The Cell Membrane Page:
EQ: What are the major components of the cell membrane, and how does its structure relate to its function?

2. What is it?
The cell membrane (or plasma membrane) surrounds every single cell & creates a barrier between the internal cell environment & its surroundings

3. What is its function?
The cell membrane allows the cell to maintain homeostasis (internal balance) by controlling what enters & exits the cell

4. Important Characteristics
Fluid Mosaic Model: Membrane structures float in and around each other like boats on water Selectively Permeable: Some materials can pass through the membrane, but some cannot

5. Structure: Membrane
Called the phospholipid bilayer – 2 layers of phospholipids
Phospholipid – Phosphate group + glycerol + 2 fatty acid chains

7. Structure: Membrane Components
OUTSIDE THE CELL
Glycoprotein
Glycoprotein
Glycolipid
Carbohydrate
Protein Channel
Cholesterol
Transmembrane Protein
Peripheral Protein
Cytoskeleton
INSIDE THE CELL

8. Membrane Components: Carbohydrates
Carbs are found on the surface of every eukaryotic cell & allow for cell recognition (like an ID tag) Cell Recognition: Ability of a cell to distinguish one cell from another
Important For:
Cell signaling
Immune System – how our WBCs recognize foreign pathogens
Organ & Tissue growth & development

9. Membrane Components: Cholesterol
Cell Membrane must be fluid & flexible – consistency is like olive oil
Cholesterol helps maintain the fluidity, permeability, and strength of the membrane

10. Membrane Components: Proteins
Many Functions for proteins! They include: transport proteins, enzymes (protein pumps), cell surface receptors, & more!

11. Membrane Components: Proteins

12. Membrane Components: Proteins

13. Artificial protein channel created with a carbon nanotube last year
Artificial protein channel created with a carbon nanotube last year! The nanotube is the gray structure & the gold structure is DNA entering a cell