Unit Four - Cells - Cell Membrane Transport Flashcards
Definition of Passive Transport (3)
- No Energy
- Moves Hi - Lo
- Goal: Reach Equilibrium
Definition of Active Transport (2)
- Use E
- Lo to Hi
What are the 3 types of passive transport?
- Diffusion
- Facilitated Diffusion
- Osmosis
Definition of Diffusion (2)
Definition, Dependence
- Movement of molecules across CM
- Dependent on concentration gradient & equillibrium
Synonym for Dynamic Equilibrium
No Net Change/Homeostasis
Meaning of “No Net Change” (4)
- Despite constant movement of molecules
- The total amount of molecules
- On both sides of the membrane
- Are the same
What happens to the molecules when it finally reaches dynamic equilibrium in diffusion? (3)
- There is a constant movement/ exchange of molecules
- There is no net change occurring
- Dynamic Equilibrium is still maintained
Are molecules dependent on each other when moving along a gradient?
Each molecule is only dependent to its own classification of molecules
Definition of Concentration Gradient
Difference in concentration of substances between two regions
Definition of Facilitated Diffusion (2)
Definition & Effect
- Diffusion w/ a transmembrane protein
- Increase in rate of diffusion
What are the 3 types of carrier proteins?
- Uniport
- Symport
- Antiport
What is an uniport carrier protein? (2)
- Transport 1 type of mol.
- In 1 direction
What is an symport carrier protein? (2)
- Transport 2 types of mol.
- In 1 direction
What is an antiport carrier protein? (2)
- Transport 2 types of mol.
- In 2 directions
Definition of Osmosis
Diffusion of Water across CM
What is the main factor that contributes to the direction of osmosis?
Solute Concentration on sides of CM
What are the three different types of transmembrane proteins?
- Channel
- Carrier
- Gated Channel
What two types of molecules cannot pass the membrane without the aid of proteins?
- Polar Molecules
- Ions
Definition of Channel Proteins
Hydrophilic channel
Definition of Carrier Protein (2)
- Binds to solute
- Protein undergoes a change in shape
Definition of Gated Channel (2)
- Hydrophyllic Channel
- Opens/Close in response to stimulus
What are 3 selectivity filters that determines if a molecule can pass through the transmembrane protein?
- Size & Shape
- Bonds between Channel & Molecule/Ions
- Charge of Ions
How does the aquaporin channel work? (4)
- H20 travel through hydrophobic section
- Reaches narrowest part
- Binds to 2 N
- Exits/Enters Cell
How does the Sodium channel work? (2)
- Sodium ion reaches narrowest section
- Sodium gets hydrated with H20 to pass
Why can’t sodium pass through the potassium channel? (5)
- Specific arrangement of oxygen atoms in the channel bond
- Responsible for stripping H20 from K
- Oxygen DOESN’T ALIGN with Na
- Na doesn’t pass the selectivity filter due to the bond between ion and channel
Why can’t potassium pass through the sodium channel? (4)
- Although K+ also has a positive charge
- It’s TOO BIG to get hydrated with H20
- Cannot pass thru narrow section of protein
- Potassium doesn’t pass the selectivity filter due to the size
(Size)
How does the Potassium Channel work?
Channel narrows, so K+ is stripped of H20
How does the Sodium & Potassium Pump work? (10)
- 3 Na+ binds to protein
- Phosphate group is released from ATP which becomes ADP
- Phosphate group binds to the pump
- Pump goes thru a change in shape
- K+ Binding Site then Opens
- Na+ exits cell
- 2 K+ binds to protein
- Pump releases phosphate group
- Pump goes thru a change in shape
- 2 K+ enters the cell
(Maintains a Nerve at Rest)
Definition of Isotonic Solution (animal cell, 3)
- Slight Salt Concentration
- Equilibrium was achieved
- No osmosis occurred
IDEAL FOR ANIMAL CELL
What does the Isotonic Solution do to the plant cell? (3)
Cause & Result
- Not ENOUGH water enters the cell
- To reach the optimal turgor pressure
- Plants become flaccid/wilts
Definition of Hypotonic Solution (3)
- Solute Concc. is lower outside
- Solvent Concentration is higher outside
- Water ENTERS the cell (Flows hi - lo)
What does the Hypotonic Solution do to the plant and animal cell? (3)
Cause, Animal Result, Plant Result
- Water enters cell (out. hi. solvent conc.)
- Animal - Cell lyses/bursts
- Plant - IDEAL, Turgid, Crisp, Full Vacuole
Definition of Hypertonic Solution (3)
- Solute Concentration is higher outside
- Solvent Concentration is lower outside
- Water LEAVES the cell (Flows hi to lo)
What does the Hypertonic Solution do to the plant and animal cell
Cause, Animal Result, Plant Result
- Water leaves cell (in. hi. solvent conc.)
- Animal - Cell CRENATES
- Plant - Plasmolysis, Cell Death
Definition of Plasmolysis (Cause, Occurrence, Effect)
- Cause: Water loss in central vacuole
- CM pulls away from the cell wall
- Cell death
What are the two types of active transport?
- Facilitated (protein/pump)
- Bulk Transport
What is bulk transport? (3)
- Large molecules. across CM
- Can’t pass thru the CM directly
- Packaged in vesicles/vacuoles
(Can also move large quantities of a substance)
What is Active Transport via Pump? (3)
- Uses ATP
- Powers change in protein shape
- For transportation against Conc. Grad.
What are the 4 factors that affect the rate of Passive Transport?
- Temperature
- Size of Molecules
- Size of Concentration Gradient
- Number of Transport Proteins
How does Temp. affect the rate of Active and Passive Transport?
Higher Temp = Higher Rate
Molecules move faster
How does the size of molecules affect the rate of Active and Passive Transport?
Smaller Size = Higher Rate
Smaller molecules pass thru proteins/pores faster
How does the size of the concentration gradient affect the rate of Passive Transport?
Higher Gradient = Higher Rate
Farther from Equilibrium, more molecules pass thru CM
Close to Equilibrium, less molecules pass thru CM
Definition of Endocytosis
Cell takes in materials from external environment
Definition of Phagocytosis (3)
- Type of Endocytosis
- Cell engulfs large particles
- Extends its membrane around particle
(Cell EATING)
Definition of Pinocytosis (3)
- Endocytosis
- Cell engulfs extracellular fluid/dissolved particles
- Extends its membrane around solution
(Cell DRINKING)
Definition of Exocytosis
Cell EXPELS waste
Definition of Excretion
Removal of metabolic waste
(urine, sweat and exhale)
Definition of Secretion
Production and release of substances
(Saliva, Digestive Enzymes, Sebum)