Human Bio 3 Plasma Membrane Flashcards
The structure of the Plasma Membrane:
Phospholipid Bilayer / 2 layers of phospholipids
Each Phosphlipid is made up of:
Phosphate Head( Hydrophillic) Fatty Acid Tail (Hydrophobic)
Function of the Plasma Membrane:
Acts as a protective barrier for cell
Regulates what enters/exits the cell
The 2 types of cellular transportation across the Plasma Membrane:
Passive + Active Transport
Define Passsive Transportation:
Requires NO energy/ATP
2 types: Diffusion + Osmosis
Define Active Transport:
Requires energy/ATP
- Na/K Pump
- Endocytosis
- Exocytosis
Define Diffusion:
A form of passive transport
stimulated by concentration differences
Attempts to evenly distribute molecules
The Rate of Diffusion depends on:
Distance: shorter length = faster
Solute Size: smaller molecule= faster
Temperature= higher temp. =faster
Concentration Gradient= more molecules= faster
Define Concentration Gradient:
The difference in solute concentration form one area to another
The 2 types of Diffusion:
Simple Diffusion
Facilitated Diffusion
Define Simple Diffusion:
Molecules that can dissolve in lipids(fats) can esily pass through the Phospholipid bilayer
Define Facilitated Diffusion:
Proteins in cell membrane that allow water + water soluble materials to pass through
Define Osmosis:
Passive transport, WATER or fluid move ACROSS the cell membrane
Travel from high concentration to low concentration
Osmosis stops when in and out of cell are balanced
Define a Aqueous Solution:
Water + a solute
Define Osmolarity:
Total solute concentration in a Aqueous Solution