Membrane Components and Transport Processes

This set of flashcards covers membrane structure, cell junctions, laws of diffusion, and the electrochemical gradients of sodium and potassium.

Membrane components

Lipids, Proteins, and Carbohydrates

Amphipathic

has both polar and non-polar parts

Phospholipid amphipathy

polar head and a non-polar tail

Functions of cholesterol

providing stability and fluidity.

Specialized cell junctions

Desmosomes, tight junctions, and gap junctions

Membrane transport methods

Simple diffusion, Facilitated transport, and Vesicular

Fick’s Law diffusion increase factors

Concentration, Surface Area, and Permeability

Fick’s Law diffusion decrease factors

Size and Distance

Red blood cell in hypotonic solution

water moves into the cell, causing it to grow

Facilitated transport candidates

polar and small.

Carrier-mediated transport types

Symport and Cotransport.

Facilitated diffusion vs. Active transport

Both use carriers, but active transport requires energy while facilitated diffusion does not

Vesicular transport types

Endocytosis and Exocytosis.

Cation concentration at rest

Sodium is located outside the membrane and Potassium is located inside the membrane.

Concentration gradient preference

Sodium wants to move into the cell, while Potassium wants to move out of the cell.

Electrical potential movement ($V_{rest}$)

both sodium and potassium want to move into the cell

Electrical potential movement ($+40\,mV$)

both sodium and potassium want to move out of the cell

Factors for negative resting membrane potential

The sodium/potassium pump moves more sodium out than potassium in, and potassium leak channels are more permeable than sodium leak channels.