Membrane Permeability Flashcards
What is a semi-permeable membrane?
A layer through which only allowed substances can pass
What type of molecule passes straight through a phospholipid bilayer?
Hydrophobic molecules
Small uncharged polar molecules
What roles do transport processes have:
Maintainable of ionic composition
”” Intracellular pH
Regulation of cell volume
Concentration of metabolic fuels and building blocks
Expulsion of metabolic waste products and toxins
Generation of ion gradients for electrical excitability
What two graphs can give Vmax and Km?
Michaelis-mention curve
Lineweaver-burk plot (more accurate)
Active transport:
Allows transport of ions against an unfavourable concentration/electrical gradient
What is mainly responsible for the resting membrane potential?
K diffusion through leak channels
What are the three types of transport?
Diffusion
Facilitated diffusion
Active transport
What are the three types of transporter?
Uniport (one substance one direction)
Symport ( two different substances, same direction)
Antiport (two different substances, different directions)
