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A & P I > API_Exam 1 > Flashcards

API_Exam 1 Flashcards

1
Q

what molecules can move easily through the cell membrane

A

H2O
glucose
ions
urea
CO2
O2
N2
isoflurane
halothane

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2
Q

what is the respiration center of the cell

A

mitochondria

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3
Q

why can the heart last longer than any other organ without O2

A

heart muscle has 10x the oxygen

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4
Q

the outside of the lipid bilayer is ___ while the inside is ___

A

hydrophilic
hydrophobic

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5
Q

what type of drugs cross the cell membrane easily

A

lipid soluble
non polar

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6
Q

where is Na concentration higher

A

extracellular 142
intracellular 10

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7
Q

where is K concentration higher

A

intracellular 140
extracellular 4

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8
Q

where is Ca concentration higher

A

extracellular 2.4
intracellular 0.0001

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9
Q

where is Mg concentration higher

A

intracellular

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10
Q

where is Cl concentration higher

A

extracellular 103
intracellular 4

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11
Q

where are amino acids, cholesterol, phospholipids, protiens, and neutral fats higher in concentration?

A

intracellular

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12
Q

what do fats, proteins, amino acids, and cholesterol in the cell do

A

help keep the inside negatively charged

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13
Q

what drives muscle contraction

A

Na entering the cell

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14
Q

what is a transporter

A

a protein in the lipid bilayer that facilitates movement in and out of the cell

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15
Q

what type of transporter is electrically stimulated

A

voltage gated ion channels

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16
Q

what type of transporter is stimulated chemically

A

ligand gated channel

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17
Q

define diffusion

A

movement of particles from a higher concentration to a lower concentration

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18
Q

T/F diffusion transports require additional energy

A

F
facilitated diffusion requires a protein to activate but still going from high to low

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19
Q

what are the two types of diffusion

A

simple and facilitated

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20
Q

define facilitated diffusion

A

diffusion from higher concentration to lower concentration using a protien

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21
Q

what is active transport

A

movement of particles from lower concentrations to higher concentrations using ATP or energy from Na

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22
Q

T or F: active transport requires additional energy?

A

true
ATP or Na

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23
Q

how does water get in and out of the cell

A

through aquaporins

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24
Q

true or false: lipid soluble molecules require channels or proteins to cross the cell membrane

A

FALSE

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25
Q

what molecules require channels or proteins to enter the cells

A

water soluble or charged particles

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26
Q

define dispersion force

A

molecules create force against eachother

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27
Q

what is an ungated ion channel

A

leak channel

allows movement based on diffusion, determined by size shape and charge of the channel and ion

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28
Q

example of voltage gated channels

A

Na
K

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29
Q

what is an example of a chemical gated channel

A

nicotinic acetycholine receptor channels
muscarinic

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30
Q

what receptor channels are part of the sympathetic nervous system

A

alpha
beta

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31
Q

what is the neurotransmitter for the parasympathetic nervous system

A

acetylcholine

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32
Q

what does troponin I bind to

A

actin

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33
Q

what does troponin T bind to

A

tropomyosin

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34
Q

what dose troponin C bind to

A

calcium

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35
Q

what are two types of excitatory post synaptic potentials

A

temporal
spatial summation

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36
Q

what do sympathetic mechanisms increase permeability to

A

Na and Ca

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37
Q

what is the neurotransmitter for the sympathetic nervous system

A

epinephrine

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38
Q

what do parasympathetic mechanisms increase permeability to

A

Potassium

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39
Q

what packages vesicles in the cell

A

golgi apparatus

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40
Q

where does the vesicle release acetylcholine

A

synaptic cleft

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41
Q

what is a ligand gated channel

A

a transporter that requires another chemical to attach to it to make it open

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42
Q

what has to attach to ligand before sodium rushes into muscle

A

acetylcholine

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43
Q

what rushes into the muscle once acetylcholine binds to the ligand

A

sodium

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44
Q

how long does a ligand gated channel stay open

A

as long as acetylcholine is attached

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45
Q

what knocks acetylcholine off the ligand

A

acetylcholinesterase

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46
Q

what happens when acetylcholine is knocked off the ligand channel

A

the channel closes
sodium cannot get in

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47
Q

what causes contraction of the muscle

A

sodium rushing in

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48
Q

what is acetylcholinesterase

A

an enzyme that breaks down acetylcholine

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49
Q

what is acetylcholine broken down into

A

choline and acetyl coA

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50
Q

what has 20% more mitochondria than other body tissues and why

A

heart- allows it last longer without oxygen

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51
Q

what gas passes in out of cell easily making induction and recovery quicker

A

sevoflurane

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52
Q

what is the barrier, integrity of cell, and separates it from extracellular fluid

A

cell wall
Phospholipid bilayer

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53
Q

what is needed for glucose to get in the cell

A

a transporter triggered by insulin

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54
Q

what is an action potential

A

the movement of Na into cell making inside of cell more positive causing it to act

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55
Q

what receptors do muscles fire with and what neurotransmitter

A

nicotinic
acetylcholine

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56
Q

what receptors do glandular tissues use

A

muscarinic

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57
Q

what on the potassium pump takes water off the potassium molecule

A

carbonyl oxygen

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58
Q

what are Na channels lined with and what are they charged

A

amino acids
negative charge

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59
Q

what pulls water away from Na to allow it to go through the Na channel

A

amino acids

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60
Q

why is facilitated diffusion slower than simple diffusion

A

it requires a protein and has limited transporters

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61
Q

another name for facilitated diffusion

A

carrier mediated diffusion

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62
Q

what causes action potential

A

moving cell off equilibrium via stimulus

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63
Q

what happens when nerst equilibrium is attained

A

cell is at resting potential

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64
Q

what two factors influence movement of an ion

A

concentration
charge

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65
Q

what is the most important transporter in medicine

A

Na K pump

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66
Q

what is hydrostatic difference

A

applying pressure on one side results in increased energy available to cause net movement from high to low pressure

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67
Q

where do you see hydrostatic pressure

A

blood
kidneys

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68
Q

another name for sodium potassium pump

A

Na K atpase

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69
Q

what combines to form atp

A

glucose and O2

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70
Q

how does atp give off energy

A

disassociation of phosphate

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71
Q

what does sodium need to get outside of the cell after an action potential

A

active transport

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72
Q

what is it when molecules are pumped against electrochemical gradient by atp

A

primary active transport

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73
Q

define secondary active transport

A

transport driven by energy store in the electrochemical gradient of another molecule

usually Na

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74
Q

what kind of energy does secondary transport use

A

indirect energy

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75
Q

example of secondary active transport

A

sodium glucose symporter

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76
Q

how does the cell get sodium out after the action potential

A

Na K pump

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77
Q

ratio of Na and K leaving/entering cells via Na-K pump

A

3 Na out
2 K in

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78
Q

what medication inhibits Na K pump to increase sodium in the cells to increase contraction strength

A

digoxin

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79
Q

what drug class is digoxin

A

glycoside- inotrope

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80
Q

what are the functions of glycosides

A

-increase intracellular sodium
-decrease sodium gradient
-decrease sodium/calcium antiporters
-increase intracellular calcium

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81
Q

where are calcium pumps located

A

cell membrane
sarcoplastic reticulum

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82
Q

what causes microfibrils to shorten and contract

A

calcium

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83
Q

why can you read an ecg

A

positive charges fire down ventricles and positive leads pick up causing spike on ecg

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84
Q

what happens when there is nothing to transport H+ ions

A

metabolic acidosis

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85
Q

what do water and CO2 make

A

carbonic acid –> breaks off to form bicarb and H+

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86
Q

where are hydrogen pumps important

A

kidneys

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87
Q

what is a symporter

A

moves two molecules at the same time and in the same direction

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88
Q

what is the number one transporter that insulin affects

A

Glut 4

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89
Q

what blocks glut 4/ other glucose binding sites so that insulin cannot activate it

A

fat

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90
Q

what is an antiporter

A

transports substances in the opposite direction of the ion

something in, something out

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91
Q

what is transcellular transport

A

moving through a whole sheet of tissue rather than just the membrane

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92
Q

what is an example of transcellular transport

A

smooth muscle tissue

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93
Q

what is osmosis

A

diffusion of water across selectively permeable membrane to area of more substances

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94
Q

what happens when albumin leaks into abdomen and why

A

ascites due to osmosis

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95
Q

what is tonicity

A

the combining of cell with fluid

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96
Q

what is osmolarity

A

measure of concentration

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97
Q

define isotonic

A

osmotic pressure is same in solution as in the cell or tissue

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98
Q

define hypotonic

A

osmostic pressure is lower in the solution than in the cell so fluid goes into cell and it swells

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99
Q

define hypertonic

A

osmotic pressure in the solution is high so water gets pulled out of the cell and it shrinks

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100
Q

what are some causes of hyponatremia

A

increased water loss
excessive sweat
DM insipidus
decreased secretion/response to ADH

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101
Q

what is voltage

A

measurement of potential energy generated by separate charges also known as membrane potential

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102
Q

what is a current

A

the flow of electricity from one point to another

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103
Q

what is the formula for current

A

voltage/resistance

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104
Q

what is an action potential

A

initiating the cell to do a function

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105
Q

what molecule has the most leaky channels

A

potassium

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106
Q

what is nerst equilibrium

A

when concentration and electrical charge are balanced in the cell

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107
Q

what is a regular resting membrane potential

A

-70 to-90 mv

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108
Q

why is resting membrane potential so close to the equilibrium of potassium

A

potassium is more permeable to the cell membrane, gets through quicker/easier

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109
Q

what direction does the resting membrane potential move closer to

A

towards the molecule with the greatest permeability

always K

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110
Q

what is depolarization

A

when sodium rushes into the cell to create an action potential

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111
Q

what is the resting membrane potential for skeletal muscle fibers

A

-90

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112
Q

what is the resting membrane potential for smooth muscle fibers

A

-50 to -60 mv

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113
Q

what is the resting membrane potential for neurons

A

-60 to -70 mv

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114
Q

what are glial cells

A

astrocytes

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115
Q

where are axons and pathways located

A

white matter

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116
Q

where does action potential occur (neuro)

A

nucleus of a neuron and sent down axon

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117
Q

what is repolarization

A

what happens after an action potential when cell becomes negative again and goes back to resting membrane potential

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118
Q

what is is called when the potential goes over 0 mv

A

overshoot

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119
Q

what is hyperpolarization

A

moving more negative than the resting membrane potential

“overpolarizing”

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120
Q

what needs to be reached for action potential to occur

A

threshold

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121
Q

what is a graded threshold

A

when stimulation occurs but doesnt reach actual threshold for action potential

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122
Q

what are excitatory post synaptic potentials

A

things that help enhance excitability to help graded threshold get to threshold

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123
Q

what is temporal summation

A

1 presynaptic neuron stimulating post synaptic multiple times

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124
Q

how does excitatory post synaptic potentials get membrane to threshold

A

open more Na channels

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125
Q

5 steps to action potential

A
  1. stimulus causes sodium channels to open activation gate letting sodium into cell
  2. once enough sodium is in to get cell to threshold action potential happens, all sodium channels open causing sodium to flood into cell
  3. once cell hits +30 mv, inactivation gate on sodium channels close stopping na from entering and potassium channels open letting potassium out of cell to help cell become more negative
  4. once cell gets to rmp, K channels start to close. voltage becomes more negative than rmp which is called hyperpolarization
  5. sodium potassium pumps gets 3 sodium out of cell and brings 2 potassium in. Leaky channels also aid in balancing cell to bring it back to rmp aka equillibrium
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126
Q

what is spatial summation

A

multiple presynaptic signals to one post synaptic neuron

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127
Q

where does excitatory summation occur

A

post synaptic

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128
Q

what do inhibitory post synaptics do

A

drive potassium out
decrease resting membrane potential (make it more negative)

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129
Q

what do seizure medications do

A

GABA decreases resting membrane potential(makes it more negative) so that its harder to get to threshold to have an action potential

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130
Q

do action potentials summate

A

no, constant amplitude

however, initiation to threshold can summate

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131
Q

at what mv does Na channels close and potassium channels open

A

+30 mv

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132
Q

why does hyperpolarization occur

A

potassium channels are slow to close until hitting the resting membrane potential

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133
Q

what helps correct cells are hyperpolarization

A

Na K pump

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134
Q

what ion flows out of the cells to get repolarization

A

potassium

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135
Q

what gets cells back to equilibrium

A

Na K pump

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136
Q

how is an action potential initiated

A

depolarization

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137
Q

what channels do action potentials rely on

A

voltage gated channels

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138
Q

what changes during action potentials

A

permeability of cell

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139
Q

what is true about action potentials conduction velocity

A

it is constant
large diameter= fast conduction
small diameter= slower conduction

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140
Q

which conduct faster: myelinated or unmyelinated

A

myelinated

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141
Q

what is propagation of action potential

A

opening of sodium channels that depolarize adjacent membrane that opens more sodium channels

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142
Q

what is propagation

A

spread of the action potential along the axon

works with depolarization and repolarization

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143
Q

what are schwann cells

A

they surrond the nerve axon forming a myelin sheath

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144
Q

what is between each myelin sheath

A

node of ranvier

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145
Q

how does myelin sheath increase conduction velocity

A

action potential jumps from node of ranvier to node of ranvier rather than cell to cell

need less action potential to move

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146
Q

what is an autoimmune disease where myelin sheath is destroyed

A

multiple sclerosis

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147
Q

what is excitatory post synaptic potential

A

part of temporal summation

synapse builds on itself to get to threshold

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148
Q

what are distant synapses whose epsp’s overlap

A

spatial summation

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149
Q

what is an inhibitor post synaptic potential

A

temporary hyperpolarization (more neg than RMP) cause by flow of negative ions into post synaptic cells

makes it unlikely that action potential will occur

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150
Q

what are all virtually all neurotransmitters

A

ligands

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151
Q

list parts of muscle largest to smalled

A

muscle
fascicles
muscle fiber
myofibrils

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152
Q

what is the outside of lining of the muscle fiber

A

sarcolema

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153
Q

what muscular structure does contraction occur

A

myofibril

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154
Q

what are the thin parts of the myofibril

A

actin

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155
Q

what are the thick parts of the myofibril

A

myosin

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156
Q

where is actin attached to

A

z disk

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157
Q

what is the space from one z disk to the next z disk

A

sarcomere

includes actin and myosin

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158
Q

what are on the twist of the actin filaments

A

protein receptor attachment sites
“active sites”

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159
Q

what are the molecules on top of actin filament

A

troponin molecules

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160
Q

what is on the end of myosin molecules

A

dual head

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161
Q

what is the i band

A

actin filaments

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162
Q

what happens to the i band during contraction

A

gets smaller

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163
Q

where does contraction occur

A

sarcomere

from one z disk to another z disk

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164
Q

what is the A band

A

actin and myosin

inside of i band on each side

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165
Q

what are myofibrils surrounded by

A

sarcoplasm

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166
Q

what are characteristics of muscle fibers

A

single cells
multi-nucleated
surrounded by sarcolemma

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167
Q

what lies between myofibrils

A

organelles: mitochondria and sarcoplasma reticulum

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168
Q

why are mitochondria important

A

where respiration occur
respiration to make O2 so it can combine with glucose to form ATP

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169
Q

what is the recoil spring that stabilizes myosin to z band

A

titin aka connectin

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170
Q

what kind of structure is titin

A

largest single polypeptide
connective tissue
coile protein in sarcomere

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171
Q

what happens when a sarcomere becomes too big in the heart

A

dilated cardiomyopathy

myosin and actin dont come in contact with each other

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172
Q

what is troponin complex

A

another name for the molecules on top on actin

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173
Q

what is braided together to form actin

A

F actin and tropomyosin

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174
Q

what are the parts of the troponin complex

A

i= binds to actin
t= binds to tropomyosin
c= binds to calcium

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175
Q

what covers active sites and prevents interaction with myosin

A

tropomyosin

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176
Q

what part of actin does myosin bind to

A

active sites ( g actin)

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177
Q

what bind to g-actin

A

myosin heads

178
Q

what happens when calcium binds to troponin molecule

A

causes tropomyosin to uncover active sites on actin allowing myosin to bind

179
Q

what happens to head of myosin is pulled back

A

stores energy from ATP

similar to mouse trap

180
Q

what is rigor mortis

A

myosin is bound to actin and waiting for ATP to come release it

muscle rigidity

181
Q

what happens when actin is moved over and myosin reaches z disk

A

full contraction

182
Q

what happens to tropomyosin when calcium gets depleted

A

covers back up receptor/active sites

183
Q

how is atp involved with power stroke

A

cocks the myosin head

stored energy

184
Q

what is active tension and what is an example

A

cannot be measured

gripping fist

185
Q

what is passive tension

A

tension pulled back a flexed muscle

fingers automatically popping back when spread out by other hands

186
Q

what is the prerequisite to contraction

A

tension

187
Q

what does the length of the sarcomere depend on

A

contraction

188
Q

when length of the sarcomere is short, what happens to tension developed

A

decreases

not every myosin is in contact with actin

189
Q

when is the greatest potential for the most tension developed in contraction

A

when every myosin head is in contact with actin so it can move further

190
Q

what happens when you stretch sarcomere too far

A

you lose contractility of muscle

191
Q

what in concentric

A

what muscle is called when it gets short with contraction

192
Q

what is excentric

A

what muscle is called when it gets longer/hyperextended

193
Q

what is isometric

A

when you can strain and cant shorten or lengthen muscle

194
Q

when one myofibril makes a contraction

A

twitch contraction

195
Q

what kind of fibers have rapid rates of shortening

A

fast or white fibers

muscles around the eye

196
Q

what kind of fibers have slow rates of shortening

A

slow or red fibers

ex: soleus

197
Q

what determines if fast or slow muscle fibers are activated

A

the stimulus sent to them

198
Q

what muscle fiber has longest sustaining power

A

slow fibers because they have more mitochondria

199
Q

what makes slow muscle fibers unique

A

type 1-
many mitochondria,
oxidative,
smaller diameter,
high myoglobin
high capillary density
low glycolytic enzyme

200
Q

what makes fast muscle fibers unique

A

type II
few mitochondria
glycolytic
large diameter
low myoglobin
low capillary density
high glycolytic enzyme

201
Q

a collection of muscle fibers is innervated by a single ____

A

neuron

202
Q

what part of the spinal cord does motor stimuli come from

A

ventral horn aka anterior horn

203
Q

how does the brain send a stimuli through spinal cord

A

synapse on neuron (in gray matter) sends out stimuli out through action potentials

204
Q

what is frequency summation

A

results from increase in frequency of contraction of a single motor unit

205
Q

what is multiple fiber summation

A

results from an increase in number of motor units contracting at the same time

206
Q

what is force summation

A

an increase in contraction intensity as a result of additive effect of individual twitch conditions

207
Q

what happens when you increase frequency summation

A

tetany state

full contraction

208
Q

muscles are always in a state of partial ____

A

contraction aka tone

209
Q

what system do you affect for dilation

A

inhibit sympathetic

210
Q

what is the formation of new muscle fibers

A

hyperplasia

211
Q

what is an increased in shortening capacity and increase in maximum contraction velocity

A

lengthening

212
Q

what is an increase in actin and myosin

A

hypertrophy

213
Q

what does increase in sarcomeres in a series lead to

A

faster velocity of shortening because there are more to contract

214
Q

what are some causes of atrophy

A

cast on limb
sedentary
tenotomy
neuropathy

215
Q

what is the difference between tension and contraction

A

tension is the potential a muscle has to contract

216
Q

where does an axon going to a muscle come from

A

anterior horn of the spinal cord

217
Q

what is between the axon and the target

A

synaptic cleft

218
Q

what is the invagination in the subneural cleft aka the motor endplate membrane

A

synaptic trough

219
Q

what increases the surface area of post synaptic membrane

A

synaptic trough in subneural cleft

220
Q

what is at the top of the subneural clefts

A

ach gated channels

221
Q

what is at the bottom of the subneural cleft

A

voltage gated channels

222
Q

where are there large amounts of acetylcholinesterase

A

synaptic cleft

223
Q

what kind of receptors are ach gated channels

A

nicotinic

224
Q

what kind of channels are nicotinic receptors

A

ligand gated

225
Q

what are ANS systems, their neurotransmitters and receptor sites

A

PNS-acetylcholine-nicotinic/muscurinic

SNS-epinephrine- alpha/beta

226
Q

in what systems do muscles work off of acetylcholine

A

somatic and PNS

227
Q

what receptor sites are always tied to muscle

A

nicotinic

228
Q

what receptor sites are generally tied to glandular tissues

A

muscarinic

229
Q

what are terms for acetylcholine channels

A

ach channel
ligand gated
nicotinic

230
Q

Describe how ach is released from the motorneuron

A
  1. action potential (sodium floods in making cell positive)
  2. sodium making cell positive causes calcium channels at terminal endplate of axon to open which lets calcium in
  3. Calcium causes protein on terminal end and protein on vesicle to bond
  4. Vesicle is opened by bonding and AcH is released
231
Q

at subneural cleft, what happens with the different channels to open them

A
  1. ACH receptors are opened by ACH that was released from pre-synaptic membrane
  2. Sodium rushes in through ACH channels
  3. Cell becoming more positive by sodium opens up voltage gated Na channels letting even more sodium in
  4. cell/muscle becoming more positive= action potential
232
Q

how does acetyl choline get deactivated off ligand channel

A

acetylcholinesterase

233
Q

what can go through ach gated/nicotinic/ligand gated channel

A

sodium, potassium, calcium

234
Q

what does botulinum toxin do

A

decreases release of ach to decrease muscle contraction

235
Q

what does curare do

A

blocks nicotinic ach receptors by competing for binding site

236
Q

what are some ach like drugs and how do they work

A

carbachol/nicotine- activate nicotinic ach receptors, NOT DESTROYED BY ACHE= prolonged effect

237
Q

What are some anti ach inhibitors and how do they work

A

neostigmine, physostigmine, diisopropyl= block degradation of ach= prolonged effect

238
Q

what autoimmune disease is characterized by presence of antibodies against nicotinic ach receptor which damages or destroys them creating paralysis

A

myasthenia gravis

239
Q

what autoimmune disease results from autoimmune attack against voltage gated calcium channels on presynaptic motor nerve terminal so ach is not released from vesicle

A

lambert eaton myasthenic syndrome

240
Q

where does action potential come from to stimulate muscle

A

anterior horn of spinal cord

241
Q

what is around sarcoplasmic reticulum

A

sarcolemma

242
Q

what are tubes through sarcolemma that penetrate the muscle fiber and are filled with extracellular fluid

A

t tubules

243
Q

what transmit action potentials deep into the muscle fiber

A

t tubule

244
Q

what are enlarged areas of the sarcoplasmic reticulum surrounding the transverse tubules

A

terminal cisternae

245
Q

what is the intracellular storage compartment for calcium

A

sarcoplasmic reticulum

246
Q

what are the structures of the t tubule/sr system

A

sarcolemma surrounds sarcoplasmic reticulum which surrounds myofibril
terminal cisternae surrounds transverse tubule which runs through muscle fiber

247
Q

what is a part of the sarcoplasmic retiuculum

A

terminal cisternae

248
Q

what is stored in the sarcoplasmic reticulum and terminal cisterne

A

calcium

249
Q

where does action potential go through sr system

A

through t tubule

250
Q

what is the cork that fill the holes on the terminal cisterne

A

ryanodine channel

251
Q

what does the protein connect the ryanodine with on the t tubule

A

dihydropyridine

252
Q

what is a voltage channel on t tubule

A

dihydropyridine

253
Q

what happens when action potential comes down t tubulein SK muscle

A

sodium from action potential causes dhp to open which pulls ryanodine out of terminal cisterne which release calcium out of terminal cisterne

254
Q

where does calcium that comes from terminal cisterne go to

A

troponin receptor site on skeletal muscle

255
Q

what is the large calcium attracting protein in terminal cisterne/sarcoplasmic reticulum

A

calsequestrin

256
Q

why is calsequestrin important

A

draws calcium back into sarcoplasmic reticulum to stop muscle contraction

257
Q

what are the events of ec coulpling in the cardiac muscle

A

-ap moves through t tubule
-calcium DHP receptors are activated releasing a small amount of Ca into fiber
-Ca binds to ryanodine receptors directly, releasing large amounts of Ca from terminal cisternae
-Calcium goes to troponin molecules to activate muscle contraction
-Calcium is attracted to calsequestrin to come back into terminal cisterne and contraction is terminated

258
Q

what are the events of ec coupling in skeletal muscle

A

-ap moves through t tubule
-Na from action potential causes voltage DHP receptor to open which pulls ryanodine cork with it which releases calcium from terminal cisternae
-Calcium goes to troponin to activate muscle contraction
-Calsequestrin attracts calcium to come back into terminal cisterne and ryanodine shuts it in

259
Q

Why do you need to give calcium slow

A

could give a heart attack, opens ryanodine receptors causing lots of contractions

260
Q

What drives cardiac muscle vs skeletal muscle ec coupling

A

calcium vs na (voltage)

261
Q

what is ca release proportional to in skeletal muscle

A

membrane voltage

262
Q

what is ca release proportional to in cardiac muscle

A

calcium entry into ryanodine receptor

263
Q

what has decreased cases of malignant hyperthermia

A

sevoflurane

264
Q

what triggers malignant hyperthermia

A

inhaled anesthetics isoflurane and halothane

265
Q

what causes malignant hyperthermia

A

constant leak of SR calcium through ryanodine receptor–causes uncontrollable muscle contractions

266
Q

what system drives smooth muscle contractions

A

autonomic nervous system

267
Q

name some places where smooth muscles are found

A

vasculature, intestines

268
Q

what are sheets of smooth muscles working together with one nerve innervation that stimulates all cells/muscles

A

unitary/visceral

269
Q

what are tissues made of discrete bundles of cells which are densely innervated. They each have their own nerve that stimulates them

A

multiunitary

270
Q

what is an example of multiunitary smooth muscle

A

iris

271
Q

what is an example of unitary smooth muscle

A

small intestine

272
Q

what are some characteristics of smooth muscle

A

operates over large lengths, energy efficient, maintain force for long periods, myogenic, calcium action potentials, poorly developed sr

273
Q

is smooth muscle striated

A

no, but skeletal muscle is

274
Q

what is a dense body in a smooth muscle equivalent to in a skeletal muscle

A

z disk

275
Q

what connects dense bodies in smooth muscle and is a thick fibrinous cord

A

intermediate filament

276
Q

what connect intermediate filaments in smooth muscle

A

dense bodies

277
Q

what brings tissue together when a smooth muscle contracts

A

dense bodies

278
Q

where do actin and myosin lay in smooth muscle

A

between dense bodies

279
Q

what is a latch state in smooth muscle

A

maintaining force for long periods of time- hours, days, weeks

280
Q

what is myogenic in smooth muscle

A

being spontaneously active

281
Q

what is delayed during a latch state

A

phosphorylation

282
Q

what provides electrical coupling in smooth muscle

A

gap junction

283
Q

what is a vesicle comparable to in smooth muscle

A

varicosity

284
Q

what would a parasympathetic (ACH) release have on intestinal smooth muscle

A

increases digestive activity

285
Q

does smooth muscle have troponin

A

No, calcium binds to calmodulin instead

286
Q

what phosphorylates the light chain

A

myosin light chain kinase

287
Q

what is myosin light chain kinase

A

enzyme that breaks down ATP, initiates contraction

288
Q

describe ec coupling of smooth muscle

A

-stimulus comes to smooth muscle
-calcium pump calcium from ECF/SR to inside cell
-calcium binds to calmodulin which stimulates myosin light chain kinase (MLCK)
-MLCK phosphorylates (takes 1 ATP) MLC which is on myosin head which activates myosin head causing powerstroke (contraction)
-released by having myosin light chain phosphatase (MLCP) knocks of phosphorus = relaxation
-ATP is used to drive calcium out of cell into ECF or back into SR

289
Q

where is myosin light chain located

A

myosin head

290
Q

what activates vs deactivates myosin in smooth muscle

A

activate= MLCK
deactivate= MLCP

291
Q

how many atp are needed in smooth muscle vs skeletal muscle

A

smooth= 2, skeletal=1

292
Q

what does calcium bind to in smooth muscle vs skeletal muscle

A

calmodulin vs troponin

293
Q

what are endocrine hormones

A

hormones released into blood stream to stimulate activity elsewhere

294
Q

what are paracrine (exocrine) hormones

A

only effects neighboring cells, doesn’t get in blood

295
Q

what are the four things that control smooth muscle

A

endocrine, paracrine, local nervous system (ans)

296
Q

what are the three types of tissue in the heart

A

atrial, ventricular, conductive

297
Q

what tissue separates the atria and ventricle

A

fibrinous tissue

298
Q

why is the fibrinous band of tissue between atrium and ventricle important

A
  1. allows independent contraction of each other
  2. allows atrium to full empty into ventricle
299
Q

what is a group of tissues working together

A

syncytium

300
Q

what are part of the conductive tissues of the heart

A

sa/av node, purkinje fibers, bundle of his

301
Q

What muscles have striations

A

skeletal and cardiac

302
Q

what initiates action potential in cardiac muscle and what stimulates troponin

A

sodium, calcium

303
Q

what are bands on cardiac muscle that are similar to z disk of skeletal muscle

A

intercalated disks

304
Q

what is the role of intercalated disks of cardiac muscle

A

contracts from one intercalated disk to another

305
Q

what makes another cell fire without having action potential in cardiac and smooth muscle

A

gap junction

306
Q

what type of smooth muscle has gap junctions

A

unitary smooth muscle

307
Q

where are gap junctions located in cardiac muscle

A

intercalated disks

308
Q

why do atrium and ventricle contract at the same time

A

gap junctions

309
Q

what is resting membrane potential of cardiac muscle

A

-90mv

310
Q

how long does plateau last in ventricular muscle

A

0.2-0.3 seconds

311
Q

why does a plateau occur in ventricular muscle

A

calcium that initiates ryanodine

312
Q

what initiates stimulus to beat the heart

A

sa node- pacemaker of the heart

313
Q

explain ventricular muscle action potential route

A

-fast sodium channels open raising membrane potential
and then slow calcium channels begin to open
-potassium channels open at peak so potassium can leave
-a few more calcium channels then open which allows more calcium in
-potassium channels open more letting out more potassium and calcium channels close causing repolarization
-resting membrane potential

314
Q

what is happening during plateau of resting membrane potential***

A

calcium is going in and potassium is coming out

315
Q

what are characteristics of calcium channels in ventricular action potential

A

slow to open, slow to close

316
Q

in what phase can cardiac muscle cannot be re-excited

A

refractory period

317
Q

what causes rhythmicity of the heart

A

refractory period- no action potentials

318
Q

whats the difference between skeletal muscle action potential and cardiac muscle action potential

A

plateau, calcium is associated with cardiac, voltage is associated with skeletal

319
Q

what happens when there is no refractory period

A

a fib or v fib

320
Q

what is ventricular muscle stimulated by action potential and contracting

A

systole

321
Q

what is ventricular muscle reestablishing sodium, potassium, and calcium gradient and is relaxing

A

diastole

322
Q

what does p corresond to in heartbeat

A

atrial contraction

323
Q

what does qrs correspond to in heartbeat

A

ventricular contraction

324
Q

what does t on ekg correspond to in the heartbeat

A

ventricular repolarization

325
Q

when does contraction occur

A

depolarized state

326
Q

where on ekg does s3 occur

A

between t and p wave

327
Q

trace the flow of blood through the heart

A
  1. surperior/inferior vena cava, 2. right atrium, 3. tricuspid valve, 4. right ventricle, 5. pulmonary valve, 6. pulmonary arteries, lungs, 7. pulmonary veins, 8. left atrium, 9. mitral valve, 10. left ventricle, 11. aortic valve, 12. aorta
328
Q

during ventricular diastole, how does blood get from the atrium to the ventricles and how much

A

75% through gravity and 25% through atrial contraction

329
Q

when ventricles first start to contract, what does blood do to mitral and tricuspid valves

A

closes them off

330
Q

what is the time after ventricles have first started to contract, shutting the bicuspid and tricuspid valves, but haven’t built up enough pressure to open aortic and pulmonary semilunar valves

A

isovolumetric contraction

331
Q

what is it called when semilunar valves are both shut but there hasn’t been enough pressure yet to open bicuspid or tricuspid valves

A

isovolumetric relaxation

332
Q

how long does ventricle contract for on ekg

A

qrs through the end of t wave

333
Q

what is a measure of action potential beginning with contraction on ekg

A

qrs

334
Q

when do av valves open on ekg

A

end of t wave

335
Q

what is s3 sound

A

heard during early diastole when blood starts filling ventricle by gravity

336
Q

what is the dicrotic notch

A

brief rise in aortic pressure as blood hits off closed valve

337
Q

what occurs during ventricular diastole in the cardiac cycle

A

isovolumetric relaxation, av valves open, atrial systole

338
Q

what happens during ventricular systole

A

isovolumetric contraction, bicuspid/tricuspid valves close, aortic valve opens, ejection, aortic valve closes

339
Q

what is a normal end diastolic volume and what is that

A

120 ml- capacity of blood available in ventricle before systole

340
Q

what is a normal end systolic volume

A

50ml- amount of blood left in ventricle after it has contracted

341
Q

what is a normal ejection volume aka stroke volume

A

70ml

342
Q

how do you calculate ejection fraction

A

ejection volume/end diastolic volume
- 70/120ml= 58%

343
Q

what are the four factors effecting cardiac output

A
  1. Heart rate
  2. contraction (ef)
  3. preload (volume)
  4. afterload
344
Q

what is afterload

A

resistance left ventricle must overcome to circulate blood

345
Q

what is preload and how can you increase it

A

volume of blood in ventricle and end of diastole- IV fluids

346
Q

what is amount of blood ejected with each ventricular beat

A

stroke volume

347
Q

what is the equation for cardiac output

A

heart rate x stroke volume
normal = 70/min x 70ml= 4900 ml/min or 5L/min

348
Q

if Hr=100, edv= 180ml, esv= 20 ml, what is cardiac output

A

stroke volume= 180-20= 160ml per ejection
100 bpm x 160ml= 16000ml/min

349
Q

how do you calculate ejection volume

A

end diastolic volume - end systolic volume

350
Q

what can cause an increase in afterload

A

aortic stenosis (calcium buildup in semilunar valves), hypertension

351
Q

what is frank starling law

A

The greater the stretch on the myocardial fibers, the greater the force with which they will contract. (ex. stretching a rubber band).

352
Q

what happens in dilated cardiomyopathy

A

myofibrils have been stretched too far, actin isn’t touching myosin, muscle becomes thin and weak

353
Q

the higher the afterload_______________

A

the lower the cardiac output

354
Q

what can increase/decrease afterload

A

vasoconstrictor/vasodilators to increase/decrease resistance

355
Q

what causes the incisura/dicrotic notch

A

aortic valve closing causing increased pressure

356
Q

what are chordae tendinae attached to and why

A

papillary muscles and bicuspid/tricuspid valves- keeps the valves from prolapsing

357
Q

do a-v valves or semilunar valves have higher velocity

A

semilunar- smaller openings

358
Q

how can increased heart rate decrease cardiac output

A

beating too fast to allow for filling during diastole

359
Q

what does excess potassium cause in the heart contractility

A

decreased contractility

360
Q

what does increased/decreased calcium cause in heart

A

increase=spastic contraction
decrease= cardiac dilation

361
Q

what induces action potential in smooth muscle

A

calcium induced

362
Q

why is it important that smooth muscle has a poorly developed sarcoplastic reticulum

A

it means it has to get calcium from extracellular sources

363
Q

where are varicosities located

A

terminal axons

364
Q

what is the difference between vesicle and varicosity

A

varicosities can hold more than one neurotransmitter

365
Q

what system drives skeletal muscle activation

A

somatic

366
Q

what drives cardiac and smooth muscle activation

A

autonomic

367
Q

what is an activator of enzymes in smooth muscle

A

calmodulin

368
Q

how does myosin become energized in smooth muscle

A

phosphorylated first so then it can break down ATP

369
Q

what is simple diffusion dependent on

A

lipid solubility and concentration gradient

370
Q

how do water soluble molecules get into the cell

A

transport channels via transport proteins

ion channels

371
Q

what allows glycerol, urea, and ammonia across the cell membrane

A

aquaglycerporins

372
Q

what strips water molecules from potassium molecules

A

carbonyl oxygens

located in selective channels

373
Q

why is the Na K pump important

A

-pumps Na ions out and K ions in (3Na:2K ratio)

-plays critical role in regulating osmotic balance by maintaining NA-K balance

-pump is activated by an increase in CELL VOLUME

374
Q

where are Ca ATpase located

A

cell membrane and sarcoplastic reticulum

maintains a low cytosolic Ca concentration

375
Q

where are H ATPase found

A

kidneys, GI

concentrates ions up to 1 million fold

376
Q

tonicity vs osmolarity

A

tonicity depends on the properties of both the membrane and the solute

osmolarity expresses the concentration of a solution

377
Q

why is the cell so permeable to K ions?

A

because of carbonyl oxygen

378
Q

what does an increase in extracellular K concentration cause?

A

increases the excitability of the cell because the resting membrane potential is closer to the threshold potential

379
Q

what is the effect of low plasma calcium on threshold potential

A

threshold potential becomes more negative

this causes more excitability in the cell

380
Q

which ion(s) manipulates resting membrane potential

A

Na and K ions

381
Q

which ion(s) manipulates threshold potential

A

calcium ions

382
Q

how does low Ca levels cause tetany

A

Low Ca causes excitability of nerve axons causing Na channels to open following a very small increase in the Vm

383
Q

how do Ca ions affect Na channel

A

bind to the exterior surfaces of voltage gated Na channel

a decrease in # of Ca ions reduces the voltage level (threshold) required to open the Na gate

the threshold potential is more negative and more excitable

384
Q

what is one of the deadliest electrolyte disorders and why

A

HYPERkalemia

bc of deadly cardiac arrhythmias

385
Q

how does HYPERkalemia affect the cell

A

High K makes the resting membrane potential less negative (raises the resting membrane potential) making it closer to the threshold for depolarization

386
Q

what are some basics of the action potential

A

-all or nothing event
-constant amplitude
-initiated by depolarization
-involves changes in permeability
-relies on voltage-gated ion channels

387
Q

what is the function of action potentials

A

-deliver sensory information to CNS
-information encoding
-rapid transmission over distance (nerve cell APs)
-AP initiate various cellular responses

388
Q

what fibers conduct pain sensations

A

nonmyelinated c fibers

389
Q

during the upstroke of the AP what are the changes in the cell permeability

A

Na permeability increases due to opening of Na channels

390
Q

what changes in the cell permeability in the downstroke of the AP

A

Na permeability decreases and K permeability increases

this is due to Na channel inactivation and opening of K channels

391
Q

why does hyper polarization occur

A

there is a delay in K channel closure

392
Q

what determines the permeability of the axon membrane

A

the permeability of axon membrane to ions is determined by the number of open channels

393
Q

define absolute refractory period

A

AP not possible due to voltage inactivation of Na channels

394
Q

define relative refractory period

A

greater than normal stimulus required to elicit AP

395
Q

what is myelination

A

Schwann cells surround the nerve axon forming a myelin sheath

396
Q

which ions are involved with excitatory post synaptic potentials

A

cation channels
Na channels

397
Q

which ions are involved with inhibitory post synaptic potentials

A

K or Cl

398
Q

inhibitory post synaptic potential

A

post synaptic cell is hyper-polarized, depresses excitability

399
Q

Label each phase of ventricular action potential

A

0: depolarization; Na floods in

1: (early repolarization) K out

2: plateau; Ca in, decreased K out

3: repolarization; outward flow of K

4: resting membrane potential

400
Q

name the phases of SA node action potential

A

0: depolarization; inward Ca current

3: plateau; outward K current

4: slow depolarization; inward Na current

401
Q

parasympathetic mechanism increases permeability to what

A

K

402
Q

SNS mechanism increases permeability to what

A

Na and Ca

403
Q

name order of muscle organization

A

Muscle
fascicles
muscle fiber
myofibril

404
Q

describe muscle fibers

A

single cells

multinucleated

surrounded by sarcolemma

405
Q

describe myofibrils

A

contractile elements

surrounded by the sarcoplasm

406
Q

what is a sarcomere

A

smallest contractile unit of a muscle fiber

z disk to z disk

407
Q

what is the largest protein in the body

A

titin

408
Q

what is the functional unit of a muscle

A

sarcomere

409
Q

what is a sarcomere made up of

A

complete A band
2 halves of the I bands

410
Q

what is unitary/visceral smooth muscle

A

sheets of electrically coupled cells which acts in unison, often spontaneously active

Ex: blood, bowel

411
Q

multiunitary muscles

A

tissue made of discrete bundles of cells which are densely innervated and contract only in response to its innervation

ex: iris, piloerectors, vas deferens

412
Q

what does latch state mean

A

maintain force of contraction for long periods of time (hours, days, weeks)

413
Q

what forms the structural backbone of the smooth muscle

A

intermediate filament

connects dense bodies together

414
Q

what smooth muscle structure is the membrane dense area that is similar to z discs

A

dense bodies

415
Q

major points about smooth muscle

A

-less complex than skeletal
-ANS fibers branch and “diffuse junctions” with underlying smooth muscle fibers
-has varicosities in the terminal axons that contain NT
-NT is secreted into the matrix coating and diffuses to muscle cells
-excitation is transmitted by Ca AP or simple diffusion of Ca into fiber
-Ca can be released from SR but has poorly formed SR

416
Q

Smooth muscle EC coupling

A

-contraction occurs by the same actin-myosin interactions as in striated muscle (sliding filament)
-the troponin complex is absent (calmodulin is very similar in structure)
-regulation is myosin (not actin) based
-myosin does not hydrolyze ATP ( to become energized) unless it is first phosphorylated (on the regulatory light chain)
-the enzyme myosin light chain kinase (MLCK) phosphorylates the light chain
-MLCK is active only in the presence of a small Ca- binding protein, calmodulin (and only when it has Ca bound)

417
Q

Contraction-relaxation (myosin based regulation

A

-initiated by calcium from ECF or SR
-Ca binds to calmodulin (instead of troponin in SKM)
-Ca-calmodulin-MLCK complex leads to phosphorylation of MLC (requires 1 atp)
-MLC is part of the myosin head
-phosphorylated myosin head binds to actin and power stroke occurs automatically
-a second ATP is required to release myosin head from actin
-cross-bridge cycling requires both MLCK and MLCP
-MLCP activity is regulated and can change calciium sensitivity (ex: if MLCP activity is high, contraction will be attenuated in the face of high Ca)

418
Q

what systems control the smooth muslce

A

endocrine, paracrine, local nervous system, ANS

419
Q

features of cardiac muscle

A

-has actin and myosin filaments
-has low resistance intercalated disks (1/400 the resistance of cell membrane)
-contraction is similar to skeletal muscle but longer

420
Q

AP of cardiac muscles

A

-resting membrane potential is -85 to -95 mV
-plateau lasts 0.2-0.3 sec in ventricular muscle

421
Q

why is there a plateau in cardiac muscles

A

Ca channels are very slow to open and even slower to close

422
Q

name the phases of cardiac action potential

A

0: Fast Na channels open then slow Ca channels

1: K channels open

2: Ca channels open more

3: K channels open more

4: resting membrane potential

423
Q

what initiates repolarization

A

Ca channels closing

424
Q

at what voltage does the Na channels close

A

+20mV

425
Q

what are the results of cardiac AP

A

-Ca release from T tubules, which are large, and a very important source of Ca
-T tubule Ca depends strongly on EXTRACELLULAR Ca concentration
-hearts T-Tubule are bigger than those in SKM (carries a lot more Ca in it) and is rich in mucopolysaccharides
-mucopolysaccharides bind and store Ca (work similar to calsequestrin)
-Ca release from sarcoplasmic reticulum (after stimulation of ryanodine receptors)

426
Q

systole in the cardiac cycle

A

ventricular muscle stimulated by action potential and contracting

427
Q

diastole in the cardiac cycle

A

ventricular muscle re-establishing Na/K/Ca gradient and is relaxing

428
Q

What is the P wave

A

atrium contraction

429
Q

QRS is what in the cardiac cycle

A

ventricular contraction

lasts through the end of the T wave

430
Q

what does the diachronic notch represent

A

Aortic valve closing

431
Q

what represents the “lub” sounds

A

AV valves closing

432
Q

what represents the “dub” sound

A

aortic valve closing

433
Q

what happens during diastole

A

-isovolumic relaxation
-AV valves open
-rapid inflow of blood
-Diastasis- slow flow into the ventricle
-atrial systole- extra blood in and follows p wave
-accounts for 10-25% of filling

434
Q

what happens during systole

A

-isovolumic contraction
-av valve closes (ventricular pressure > atrial pressure)
-aortic valve opens
-ejection phase
-aortic valve closes

435
Q

During the latter part of the ejection phase, how can blood still leave the ventricle if pressure is higher in the aorta?

A

total energy of blood leaving the ventricle is greater than in the aorta

436
Q

what are the four factors that impact CO

A

HR
Contraction
preload
afterload

437
Q

ejection fraction equation

A

ejection volume= end diastolic vol- end systolic volume

ejection fraction=ejection volume/ end diastolic volume

438
Q

CO equation

A

CO= HR x stroke volume

439
Q

Autonomic effects on the heart

A

-SNS stimualtion causes increased HR, increased contractility, and increased vascular tone
-PNS stimulation decreases HR and Decreases cardiac contractility slightly

vagal fibers go mainly to the atria

440
Q

what is the function of subneural clefts

A

-increases surface area of post-synaptic membrane
-ach gated channels at top of subneural cleft
-voltage gated Na channels at the bottom of subneural clefts

441
Q

where does the AP begin in the motoneuron

A

in the ventral horn of the spinal cord

442
Q

what is the function of gap junctions

A

allow cells to communicate to cells next to them

A & P I (4 decks)

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