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Flashcards in 9 Review Deck (44):
1

ICF is the fluid inside the cell, it is maintained by the ______

Cell membrane

2

The ECF is split into 2 compartments

1. Interstitial fluid
2. Plasma

3

What membrane separates the compartments of the ECF

Capillary walls

4

What is passive transport

Moves with gradient (H>L)
No energy needed

5

What are some types of passive transport

Diffusion
Facilitated diffusion
Osmosis

6

What is active transport

Moves against gradient (L>H)
Needs energy

7

What are the types of active transport

Primary and secondary

8

Ion channels are very specific to ____ and _____, and the flow depends on _________

Specific to ion size and charge

Flow depends on number open

9

Leak channels

Always open

10

Gated channels

Closed until a stimulus opens it

11

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

12

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

13

Voltage gated channel

Remain closed until membrane potential reaches a specific value
Remains open depending on the membrane potential and channel properties

14

Resting membrane potential is due to

Charge difference across cell membranes due to concentration gradients of ions

15

Inside of cell: _____ charge

Negative

16

Outside of the cell: ____ charge

Positive

17

What is the typical RMP of the body?

-70 mV at rest

(Range is -20 to -100)

18

What channel is the major contributor of RMP

K+ current through leak channels

19

Na-K ATPase is necessary for RMP.
____ Na moves ____
____ K moves ______

3 NA out
2 K in

20

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

21

Synapses are

Site of communication between cells

22

What are the types of synapses

Electrical (gap junctions)
chemical

23

Electrical synapses are

Direct connections between cells that allows ions to flow between

Makes a syncytium ( bunch of cells acting as 1)

24

Synaptic transmission

(Flow)

Propagation of AP> release of NT> bonding of NT to receptor> effect on postsynaptic cells

25

Excitatory post synaptic potentials (EPSP)

Depolarize cell

Result of opening Na, Ca channels OR closing K channel

Glutamate

26

Inhibitory post synaptic potentials

Hyperpolarize cell

Opening Cl or K channels OR closing Na/Ca channel

GABA, glycine

27

In order for a NT to work it must do what?

Bind a receptor

28

The effect a NT has is based on

The receptor it binds

29

Ionotropic receptors are...

Receptor is an ion channel

Open and close based on the ligand

Retinal glutamate receptors are Na/Ca channel

30

Metabotropic receptors are...

Receptors coupled to an intracellular protein

Ligand binding alters 2nd messenger numbers

Retinal glutamate receptors are Gi coupled receptor

31

Gs

Stimulate adenylate cyclase

Increase cAMP levels

32

Gi

Inhibit adenylate cyclase

Reduce cAMP

33

Gq

Stimulates phospholipase C
Makes IP3

Increases Ca levels

34

Gt

In eyes, acts like Gi except with cGMP

35

A1 receptors in eye

Pupil dilation

36

A2 receptors in eye

Reduce aqueous humor formation by reducing B2 release

37

B2 receptor in eye

Ciliary relaxation
Increase aqueous humor production

38

Parasympathetic receptors in eye

Pupil constriction
Ciliary muscle contraction
Increase aqueous drainage and reduce production

Lacrimal secretion

39

Gap junctions

Electrical connections
Little support

40

Anchoring junctions

Structural spot-weld

Cell-cell: desmosome
Cell to ECM: hemdesmosomes

41

Tight junctions make

Sheets of cells
Permeability depends on how tight the cells are held together

42

Zonula occludens

Cell membranes touch
Very restrictive
Movement is transcellular
BBB

43

Zonula adherens

Space between cell membranes varies
Filtration can occur

Kidney, blood vessels

44

Slide 31

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