Cell Physiology Cont'd

Question 1

Types of Receptors:

what are 3 other ex of ligand-gated receptors?

Answer 1

5-HT3
GABAa
Glutamate

Question 2

Types of Receptors:

what are receptors that control membrane bound enzymes called?

Answer 2

metabotropic receptors

Question 3

Types of Receptors: Metabotropic receptors

how do they work

Answer 3

when a ligand attaches to its receptor , an enzyme on the cytoplasmic surface (inside) of the membrane is activated a reaction inside the cell is accelerated by the enzyme

Question 4

Types of Receptors: Metabotropic receptors

what are the most common type of receptors that control membrane bound enzymes

Answer 4

G-protein coupled receptors

Question 5

Types of Receptors: Metabotropic receptors

what are examples of the receptors

Answer 5

GPCR
7-transmembrane
Serpentine
Muscarinic ACh receptors (are GPRC)
most adrenergic receptors

Question 6

Types of Receptors:
what type of receptors are integral plasma membrane proteins that when activated by a ligand are either enzymes themselves or part of an enzymatic complex.

Answer 6

Catalytic receptors

Question 7

Types of Receptors:

what are ex of catalytic receptors

Answer 7

Insulin
EPO
ANP

Question 8

Types of Receptors:

what type of receptors are proteins located in the cytosol or nucleus, are ligand-activated transcription factors.

Answer 8

Nuclear (intracellular) receptors

Question 9

Types of Receptors:

how do Nuclear (intracellular) receptors work

Answer 9

link extracelular signals to gene transcription in the nucleus of the cell

Question 10

Types of Receptors:

what type of drugs exert their cellular effects via the nuclear receptors

Answer 10

Steroid hormones

Question 11

What spans the thickness of the lipid bilayer

Answer 11

channels

Question 12

Proteins that span the membrane are called what?

Answer 12

integral or transmembrane proteins

Question 13

Chemicals that attach to the receptors of the cell membrane are called _____

Answer 13

ligands

Question 14

Ligands act as what (first or second messengers)?

Answer 14

first messengers

Question 15

Receptor sites are usually located where?

Answer 15

outside the cell

Question 16

membrane enzymes are generally anchored where?

Answer 16

inside the cell

Question 17

Chemicals generated inside the cell by enzymes facing inward from the cell membrane are called what? (1st or 2nd messengers)

Answer 17

Second messengers

Question 18

what is the 1 exception to the 2nd messengers. All second messengers are released into the cell except this one?

Answer 18

Acetylcholinesterase

-projects outward into the synaptic cleft so it can metabolize ACh

Question 19

take home message about receptors:

A membrane receptor usually either operates as a _____ or controls an ______

Answer 19

Channel

Enzyme

Question 20

Signal transduction:

what is it

Answer 20

the relaying of a message from the exterior to the interior of the cell

Question 21

Signal transduction:
Signal transduction using receptors involves the action of an intermediary protein messenger, which transfers the signal from the receptor to an enzyme. ___ Proteins are the best known proteins for relaying messages from receptors to enzymes

Answer 21

G proteins

Question 22

what is the name of the membrane stimulatory protein

Answer 22

Gs

Question 23

What is the name of the membrane inhibitory protein

Answer 23

Gi

Question 24

on the exterior the 1st messenger attaches to the receptor and Gs or Gi relays or shuttles information to an enzyme. What is the enzyme that it is usually shuttled to?

Answer 24

adenylate cyclase

Question 25

what is the function of the Na+ K+ pump ATPase pump

Answer 25

keep intercellular K+ high and Intracellular Na+ low

Question 26

The Na+ K+ pump uses energy derived from the breakdown of ATP to go through a series of shape changes , ultimately moving __ Na+ ions out of the cell in exchange for __ K+ ions that are transported into the cell

Answer 26

3 Na+ | 2 K+

Question 27

Remember | How many Na+ And K+ are exchanged

Answer 27

3 Na+ extruded | 2 K+ imported

Question 28

An ____ fits into a receptor and then makes something happen.

Answer 28

Agonist

Question 29

A _____fits into a receptor but has no direct effect. it prevents the agonist from attaching to the receptor so nothing happens

Answer 29

Antagonist (competative)

Question 30

Resting Potential: | where are leaky K+ channels located

Answer 30

lipid bilayer

Question 31

Continuosly open (Leaky) K+ channels are located in the lipid bilayer and permit what?

Answer 31

outward diffusion of K+ down the concentration gradient

Question 32

What controls the RMP

Answer 32

K+

Question 33

with acute hyperkalemia the diffusion gradient for K+ in reduced, b/c the rate of diffusion out of the cell is decreased what happens to the RMP?

Answer 33

the resting potential is diminished aka the cell depolarizes (RMP goes from -70 to -60)

Question 34

With hypokalemia the diffusion gradient for K+ is enhanced, b/c the rate of diffusion out of the cell is increased, what happens to RMP?

Answer 34

The resting potential is increased the cell hyperpolarizes | -- RMP goes from -70 to -80

Question 35

with polarity the (-) negative sign in front of the numerical value for the Resting potential indicated the what?

Answer 35

Polarity thus hyper polarized is MORE neg and Hypo or depolarized is more Positive

Question 36

State the steps of an Action potential

Answer 36

A) RMP at -70mV when the nerve axon depolarizes to threshold the FAST Na+ VOLTAGE GATED CHANNEL snaps open B) a massive and abrupt depolarizations occurs as Na+ influxes ( RMP +30mV) C) the fast voltage gated Na+ channels quickly shits in the inactivated state and the voltage gated K+ channels open the diffusion ok K+ out causes repolarization and restoration of the RMP at -70mV D) the Na+ K+ pump extrudes Na+ that entered the cell a d recaptures the K+ that was lost thus restoring ionic balance ** the leaky K+ channels constantly leak K+ out of cell) See page 8 in sweat book for a diagram

Question 37

in the neuron the voltage gated Na+ channels are located princiably where?

Answer 37

the axon and concerted in the nodes of ranvier

Question 38

what is the term for the period when the gated sodium channel is in the inactivated state?

Answer 38

absolute refractory period

Question 39

Know this!!! | When are 3 important clinical example r/t the absolute refractory period (inactivated state)

Answer 39

1) cardioplegia 2) SCh administration 3) LA administration

Question 40

Memory master pages

Answer 40

IA3a-b