Cell Science - Cellular Process 1 & 2 Flashcards
What does intracellular mean?
Within the cell
What does Extracellular mean?
Between the cells
E.g in blood vessels = plasma
What does solvent mean?
It’s the liquid doing the dissolving
What does solute mean?
It’s the dissolved material (particle or gas)
What does concentration mean?
It’s the amount of solute in a given amount of solvent
What does Concentration Gradient mean?
It’s the Difference in concentration between 2 area of solution
What does selective permeability mean?
Allows a living cell to maintain different concentrations of certain substances on either side of plasma membrane
What does concentration gradient mean?
Difference in the concentration of chemical from one place to another
- From inside to outside of plasma membrane
What is the Electrical gradient?
Difference on electrical charge between two regions
What is membrane potential?
It’s the electrical gradient that occurs across the plasma membrane
Why is the concentration gradient and electrical gradient important?
They are important because they help move substances across the plasma membrane
What is the electrochemical gradient?
It’s the concentration gradient and the electrical gradient on movement of a particular ion
What is the electrochemical gradient?
It’s the concentration gradient and the electrical gradient on movement of a particular ion
Name 4 types of movement across the membrane
- Passive transport
- Active transport
- Endocytosis
-exocytosis
Name 3 types of passive transport
- Simple Diffusion
- Facilitated Diffusion
- Osmosis
What is diffusion?
It’s a passive process involving the random mixing of particles in a solution due to a particles kinetic energy
What factors affect Diffusion?
- steepness of the concentration gradient:
- Temperature: higher temp means faster diffusion
- Mass of diffusing substance: larger mass of diffusing particle, slower diffusion rate
- Surface area: Larger membrane area, faster the diffusion
- Diffusion Distance: Greater distance the longer it takes
Describe Simple Diffusion
- No energy required
- Moves due to gradient: difference in concentration, pressure, charge
- Moves to equalize gradient: High moves toward low
- Depends on lipid soluability
What is Facilitated Diffusion?
It’s when solutes are too polar or highly charged to move through lipid bilayer by simple diffusion across the plasma membrane
- Requires a carrier
- goes down the concentration gradient
What does Facilitated diffusion go through
- Ion Channels
- Protein Transporters (AKA carriers)
What is the Ion Channel (Facilitated Diffusion)
Channel mediated facilitated diffusion of potassium ions (K+) through a gated K+ channel
What is a carrier in Facilitated Diffusion
- a carries is used to move a solute down its concentration gradient across the plasma membrane
What are the substances that move across the plasma membrane by carrier mediated facilitated diffusion
Glucose, Fructose, Galactose and some Vitamins
What do the carriers exhibit when the maximum transport is reached
Saturation
