bioCHEM QUIZ Flashcards
What are the methods of crossing a membrane?
- Passive transport
- No energy needed
- Solute travels down concentration gradient
- Active Transport
- coupled to ATP hdrolysis
- Solute travels against concentration gradient
What are the three modes of transport?
Antiporter
Symporter
Uniporter
What are the three categories of transport?
- Pumps perform primary tramsport
- EX: IRL a water pump fights gravity and actively pulls water to the house
- Carriers transverse the membrane without needed (extra) energy
- EX: IRL carrying a stowawat along of the ride
- Channels are used in pasive transport
- the channel opened and allowed your ship to float gently out of the gridlock from beind the dam
What is P-type ATPASE?
- Example of primarya active transport
- 4 domains
- transmembrane
- domains spans the lipid bilayer
- A/activator domain
- links the cytosolic domains to the transmembrane domain
- N/Nucleotide
- binding domain binds ATP
- P/Phosporylation
- domain accepts the phosphate from ATP
- transmembrane
What IS serca?
an example of primary active transport
Also an example of P typle ATPase
WHat is the Na/K pump?
an example of primary active transport
an exampe of P type ATPase
What are the effects of digitalis adn ouabain ?
Both lock the Na/K pump in the E2 conformations
- Keeps Na+ inside cell
- Excess Na+ then removed by exchanging with Ca2+
- Extra Ca2+ makes heart contract
WHat is MDR proteins and MSbA protein an example of?
How do ABC transporters work?
a type of primary active transport
- Empty transporter
- small moelcule binds and is trapped; ATP binding site affinity increases
- 2 ATPs bind causing eversion
- Small molecule is released
- ATP hydrolysis and release
What is NA-glucase and example of and how does it work?
- Secondary active transport
- After primary active transport creates a gradient, a passive channel or carrier allows ions/molecules to fall back down the gradient with a high value stowaway
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How does Lactose Permase work?
Example of secondary active transport
- Empty carrier, H+ binds and increases affinity for lactose
- lactose binds
- eversion
- lactose released deproteontation
- eversion
What are fACTORS that affect diffusion rates?
- Factors affecting diffusion rates
- Magnitude of concentation gradient
- Larger = faster
- size of molecule
- larger = slower
- surface area:volume ratio (Shape)
- higher = faster
- Temperature
- higher = faster
- density of solvent
- higher density = slower diffusion
- solubility of solute
- nonpolar = soluble
- longer = slower
- disance to the destination
- Magnitude of concentation gradient
How do ion channels work?
- Selectivity filter
- Ex: bacterial K+ channel
- movement results from eletrostatic repulsion
- Ex: bacterial K+ channel
- gate
- Voltage
- ligand
- stress
- application
- 5 channels work together to contract your muscles
- depolarization open svoltage gated Ca2+ channel
- Exocytosed acetylcholine opens ligand gated Na+ ligand Channels
- Local depolarization opens adjacent voltaged gated Na+ channels
- As depolarization spreads, voltage gated Ca2+ channels open
- Coupled Ca2+ released channels embedded in the SR open
- 5 channels work together to contract your muscles
What are Gap Junctions?
Example of facilitated Diffusions
allow cytoplasm sharing
no specifity filter
what are are aquaporins?
let water but not Iet ions through
