B2.1.6 - Channel Proteins for Facilitated Diffusion

What is the primary function of channel proteins in cell membranes?

facilitate the passive transport of specific molecules and ions across the cell membrane

What are 3 key features of channel proteins that enable their function?

• Selectivity: Only specific molecules or ions can pass through

• Hydrophilic Pore: The channel is lined with hydrophilic amino acids

• Bidirectional: Molecules can move in either direction depending on the concentration gradient

gated channels

channel proteins that open and close in response to specific signals

What are the 3 main types of gated channels, and what each responds to?

• voltage-gated - changes in electrical charge across the channel

• ligand-gated - when a specific molecule binds to the channel

• mechanically gated - responds to physical forces, like stretching

3 examples of physiological processes that rely on channel proteins

• nerve signalling

• muscle contraction

• water balance

role of channel proteins (TBD)

3 types of specialized channel proteins and their function

• Ion channels: Allow the passage of specific ions like Na+, K+, or Cl-

• Aquaporins: Facilitate the movement of water molecules

• Glucose transporters: Enable the transport of glucose molecules

what are 3 applications of channel proteins in medicine?

• drugs that target specific channel proteins

• development of artificial channel proteins for drug delivery

• mutations in channel proteins → genetic disorders

What disease is caused by a defect in the CFTR chloride channel?

Cystic fibrosis - thick mucus buildup in lungs