9 Review Flashcards
ICF is the fluid inside the cell, it is maintained by the ______
Cell membrane
The ECF is split into 2 compartments
- Interstitial fluid
2. Plasma
What membrane separates the compartments of the ECF
Capillary walls
What is passive transport
Moves with gradient (H>L)
No energy needed
What are some types of passive transport
Diffusion
Facilitated diffusion
Osmosis
What is active transport
Moves against gradient (L>H)
Needs energy
What are the types of active transport
Primary and secondary
Ion channels are very specific to ____ and _____, and the flow depends on _________
Specific to ion size and charge
Flow depends on number open
Leak channels
Always open
Gated channels
Closed until a stimulus opens it
Ligand gated channel
Remains closed until proper ligand binds
Remains open as long as ligand is around, closes when it removed
Fast to elicit a cellular response
2nd messenger gated channel
Remains ope as long as 2nd messenger is around, closes when it is removed
2nd messenger i made until receptor is no longer stimulated
Slower to cause a responses more diverse effects
Voltage gated channel
Remain closed until membrane potential reaches a specific value
Remains open depending on the membrane potential and channel properties
Resting membrane potential is due to
Charge difference across cell membranes due to concentration gradients of ions
Inside of cell: _____ charge
Negative
Outside of the cell: ____ charge
Positive
What is the typical RMP of the body?
-70 mV at rest
Range is -20 to -100
What channel is the major contributor of RMP
K+ current through leak channels
Na-K ATPase is necessary for RMP.
____ Na moves ____
____ K moves ______
3 NA out
2 K in
At Rest- RMP (K flux through leak channels)
Local depol. (Stimulation occurs- ligand gated Na channels)
Threshold, -60 mV (Nav channels open)
Over shoot (Na influx)
Repol (Na slows, K rises)
Hyperpol ( more K leaves)
At rest
Know this
Synapses are
Site of communication between cells
What are the types of synapses
Electrical (gap junctions)
chemical
Electrical synapses are
Direct connections between cells that allows ions to flow between
Makes a syncytium ( bunch of cells acting as 1)
Synaptic transmission
Flow
Propagation of AP> release of NT> bonding of NT to receptor> effect on postsynaptic cells
Excitatory post synaptic potentials (EPSP)
Depolarize cell
Result of opening Na, Ca channels OR closing K channel
Glutamate
Inhibitory post synaptic potentials
Hyperpolarize cell
Opening Cl or K channels OR closing Na/Ca channel
GABA, glycine
In order for a NT to work it must do what?
Bind a receptor
The effect a NT has is based on
The receptor it binds
Ionotropic receptors are…
Receptor is an ion channel
Open and close based on the ligand
Retinal glutamate receptors are Na/Ca channel
Metabotropic receptors are…
Receptors coupled to an intracellular protein
Ligand binding alters 2nd messenger numbers
Retinal glutamate receptors are Gi coupled receptor
Gs
Stimulate adenylate cyclase
Increase cAMP levels
Gi
Inhibit adenylate cyclase
Reduce cAMP
Gq
Stimulates phospholipase C
Makes IP3
Increases Ca levels
Gt
In eyes, acts like Gi except with cGMP
A1 receptors in eye
Pupil dilation
A2 receptors in eye
Reduce aqueous humor formation by reducing B2 release
B2 receptor in eye
Ciliary relaxation
Increase aqueous humor production
Parasympathetic receptors in eye
Pupil constriction
Ciliary muscle contraction
Increase aqueous drainage and reduce production
Lacrimal secretion
Gap junctions
Electrical connections
Little support
Anchoring junctions
Structural spot-weld
Cell-cell: desmosome
Cell to ECM: hemdesmosomes
Tight junctions make
Sheets of cells
Permeability depends on how tight the cells are held together
Zonula occludens
Cell membranes touch
Very restrictive
Movement is transcellular
BBB
Zonula adherens
Space between cell membranes varies
Filtration can occur
Kidney, blood vessels
Slide 31
Reveiw it
