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Anatomy > Unit 3 🧠🫀💪🏻 > Flashcards

Unit 3 🧠🫀💪🏻 Flashcards

1
Q

Propioception

A

Ability sense relative position of body parts

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2
Q

Neuron v glial cells

A

Neuron : signaling unit (most function of nervous system) function al unit transmits information from one cell to another
Amniotic (can’t divide except olfactory neurons and the hippocampus regions of the brain) (maybe to preserve learning)
Have high metabolic rates and last a lifetime amount

Glial cell : support unit

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3
Q

CNS v PNS

A

Central nervous system: associated with neurons involved in central processing located in the brain and spinal chord

Peripheral nervous system is associated with sensory input(afferent) and motor output (efferent) and connects the cns to to the body

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4
Q

PNS CNS control system system

A

Stimulus receptor afferent pathway control center efferent pathway effector response

PNS takes info form receptor to the CNS the control center which then makes a decision and sends an efferent message again the the PNS to effector which then triggers a response

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5
Q

Somatic nervous system

A

Efferent neurons

Voluntary movement of skeletal muscle

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6
Q

Autonomic neurons

A

Efferent neurons
Involuntary
Heart lungs glands etc and smooth muscles

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7
Q

Sympathetic

A

Autonomic
Involuntary
Activates the flight or fight response

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8
Q

Parasympathetic nervous system

A

Autonomic
Involuntary
Reverses the flight or fight response and helps body return to normal

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9
Q

Enteric nervous system

A

(Semi independent)
Autonomic NS
Controls GI tract
It can run independently or through modulation
Contains more more neurons the. The entire spinal chord

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10
Q

Soma

A

Cell body

Is the portion of the cell that Surrounds the nucleus and plays a role in protein synthesis

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11
Q

Dendrites

A

Short branched
Process that extends from cell body
Function to receive information
Neurotransmitter receptors

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12
Q

Axon

A

A large process that extends from the cell body
Point of origin called the axon hillock
Sends information via action signals
Axons contain micro tubules and are surrounded by myelin which surround the axon speeding up the propagation of the action potential

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13
Q

Anterograde transport v retrograde transport

A

Antero away from soma

Retro back towards soma

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14
Q

Axon terminals

A

Ending sections of the axon

Coverts the electrical signal into chemical signal (synaptic transmission) system

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15
Q

Multi polar

A

See figure 2

The normal one

Has many dendrites and one axon coming out
99% are multipolar

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16
Q

Bipolar neuron

A

Have only two processes that extend in opposite directions one is a dendrite the the other is axon

Retina of eye and olfactory system

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17
Q

Unipolar neuron

A

Have a single short process that extends from the cell body and branches into two or more processes that extend in opposite directions

Process that extends peripherally is called peripheral process and is associated in sensor reception

Process that extends toward CNS is the central process

Found in afferent division of PNS

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18
Q

Sensory neurons

A

Afferent neurons transmit info from sensory receptors towards the cns almost all sensory are unipolar

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19
Q

Motor neurons

A

Efferent
Transmit info from CNS toward some sort of effector
Typically multipolar

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20
Q

Inter neurons

A

Are located between sensory Neuron and motor neuron pathways
Involved in signal integration
Confined within cns

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21
Q

Astrocyte

A

CNS

Controls environment around the neuron

Lots of processes that tap around the blood vessels

Glycogen storage

K+ permeability

Gap junction

Neurotransmitters

Growth factors

Blood flow

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22
Q

Astrocyte glycogen storage

A

Helps store glycogen for metabolic processes and supplements the main source of auger the blood glucose level this extra storage can sustain the cns for 5to 10 min

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23
Q

K+ permeable of astrocyte

A

Active neurons loose k+ to outside which would act as a positive feed back if not for astrocyte

Take up k+ by a pump (sodium potassium pump) or cotransporters NA k cl and k cl exchangers

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24
Q

Gap junctions astrocyte

A

Coupled to each other as well as other glial cells through gap junctions

Helps modulate activity and sensitivity of cns

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25
Q

Astrocyte neurotransmitters

A

Synthesize 20 different neurotransmitters and take up excess neurotransmitters to help terminate signal at synapse

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26
Q

Astrocyte

Growth factor

A

Secrete a variety of growth factors which are important in establishing fully functioning excitatory synapses

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27
Q

Astrocytes blood flow

A

Modulate blood flow I the brain by inducing vasodilation and constriction this can occur through gap junction between astrocytes and endothelial cells of brain blood vessels

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28
Q

Oligodendrocytes

A

CNS
Maintain myelin sheaths
Which insulates and propagates along the axon without being spread to other axons

15-30 processes

Between each raping are nodes of ranvier

Create salutary conduction

And help cluster volatge gaskets NA channels at the nodes

Regulate ph of cns

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29
Q

Multiple sclerosis

A

MS is a autoimmune disease where the body attacks oligodendrocytes resulting in reduction of myelin
Which can decrease conduction speed
Which can result in loss of sensory perception and motor control

2x in women then men

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30
Q

Ependymal cells

A

Line cavities of cns
They produce cerebral spinal fluid and are important barriers between the csf and brain extracellular space these cells beat their cilia to help circulate spf

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31
Q

Micro glial cells

A

Rapidly activated in cns in response to injury

Injury causes them to change shape and become phagocytic

Important I. Presenting antigens and lynphocytes in response to infection.

Although helpful they can also be toxic to neurons and can result in long term damage

Some medical interventions inhibit microglial activity

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32
Q

Schwann cell

A

PNS

Myelinating cell

Provides myelin for only single segment of axon

Myelin appearance and function the same in PNS and cns

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33
Q

Satellite cells

A

Help maintain external chemical environment of PNS

Very similar to astrocytes in CNS

But in addition are highly sensitive to injury and inflammation

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34
Q

Synaptic transmission

A

Movement of signal across synapses via neurotransmitters

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35
Q

Chemical synapses

A

Occur when neural membranes are very close together but remain distinct, leaving space

Use neurotransmitters to communicate

Pre and post terminals contain things to send and receive signal

Pre contains large amounts of vesicles packed with neurotransmitters when action p arrives opens ca channels which trigger then induce exocytosis on neurotransmitters

The nuerotrans then bind to receptors on post and induce confirmational shifts which causes the receptor to act like a pore letting in ions

Enzymes break down neurotransmitters turning off the signal the parts of neurotransmitters are then retaken by pre terminal and sent back to soma

Ex of enzyme that turns off is acetylcholinesterase that breaks down the neurons transmitter acetylcholine

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36
Q

Electrical synapses

A

Over when membranes are linked together (gap junction) via specialized protiens (connexins)
Allow corn flow of ions quickly from one cell to another

Ex heart muscle

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37
Q

Presynaptic termial

A

Part that releases neurotransmitters into synaps

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38
Q

Postsynatpic terminal

A

Part of neuron the recives neurotransmitters on other side of synapse

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39
Q

Synaptic cleft

A

Narrow space between the pre and post terminal

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40
Q

Effect on post synapse excitatory and inhibitory

Epsp

Ipsp

A

Last for a few seconds and the. Potential goes back to resting

Normally not sufficient alone
Excitatory
Epsp- depolarization - enough change to set off action potential

Inhibitory
Ipsp- hyperpolarization -

This occurs at axon hillock

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41
Q

Special summation

A

The many epsp and ipsp combine at the soma which results in a much larger voltage charge

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42
Q

Temporal summation

A

Many epsp from the same synapse can also combine if they arrive in taped succession

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43
Q

Post synaptic receptors

A

Hundreds of different neurotransmitters and receptors

Types :
Chemically gated ion channels
When open the item type will determine which ion flows in and whether it is epsp or ipsp

Second message systems results in cascade of of interactions the type of cascade will result in either an excititory response or inhibitory

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44
Q

Excititory synapse

A

Most I. The brain use glutamate or apsarate as neurotransmitters

Bind to non selective cat ion channels that allow for NA or k to pass

Many of these can f
Reach threshold and create action potential

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45
Q

Long term potentiation

A

Subset of synapses

Capable of forming memories by increasing strength and and activity of synapse

Involves glutamate and a receptor known as NMDA receptor ( unique in that it is both ligand and voltage gated)
When activated by ligands become permeable to NA if the charge is suffecient becomes permeable to ca as well
Which triggers a second messenger cascade that results in an increase in the number of glutamate receptors which the. Increases strength of the synapse

It can last for months weeks or even years wether or not synapses is continually used

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46
Q

Inhibitory synapses

A

The excitability is governed by neurons is essentialy governed by balance of excite and inhibitory

Main neurotransmitters are GABA and glycine both bind to receptors that result in the increase of conduction of cl because it is - and moves into the cell makes it oppose depolarization

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47
Q

Modulatory synapses

A

Are those that can be primed by neurotransmitters so they are able to respond more powerfully to other inputs

For example norepinephrine (has little effect alone) but when exposed first to norepinephrine reacts more powerfully to glutamate

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48
Q

Functions of muscles

A 
Movement
Maintenance of posture
Respiration 
Heat generation
Communication 
Constriction of organs and blood vessels
Pumping blood

More ex.
Protect fragile organs
Maintains integrity of body cavity

And more

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49
Q

Muscle function movement

A

Skeletal muscles yank and pull on out skeleton resulting in movement

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50
Q

Maintenance of posture function o muscle

A

Without much conscious control muscles generate contractile force that allows them to maintain an erect or seated position also known as posture

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51
Q

Respiration function of muscle

A

Via diaphragm air is driven into and out of body

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52
Q

Heat generation

A

Contraction of muscles generate heat which helps maintain homeostasis

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53
Q

Muscle function communication

A

Allows us to talk write gesture and convey our emotional state

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54
Q

Muscle function constriction of organs and blood vessels

A

Nutrients move through our digestive system urine is passed out of the body and and secretions are propelled out of glands by contraction of smooth muscle

Also constriction of blood vessels regulate bp

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55
Q

Pumping blood function muscle

A

Heart pumps blood through the body

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56
Q

All muscles have the following properties

A

Contráctility: the ability for the muscle to shorten (for one muscle to contact another must extend)

Excitability: has the ability to respond to a stimulus when delivered from a motor neuron and hormone

Extensibility: the ability for the muscle to be stretched (lack of extensibility is spasticity)

Elasticity: ability to recoil or bounce back to the muscles original length after being stretched

57
Q

Skeletal muscle

A 
Striated 
Voluntary
40% of our weight
There are many nuclei in each skeletal muscle cell which are pressed against the sarcolema because of all the myofibrils 
And myofilaments
58
Q

Smooth muscle

A

Wildly distributed throughout body
Found in hollow organs tubes and blood vessels, airways inside the eye

Lacks striations
Involuntary

Aka visceral muscle

Autorythmic

59
Q

Cardiac muscle

A

Only found in the heart
Striated
Involuntary

Autorhythmic : capable of contracting spontaneously or without neurosurgeon or Hormonal input

60
Q

Muscle fiber

A

Skeletal muscle cell which develope as many myocytes fuse together

Same diameter as hair follicle

61
Q

Fascicles

A

Are bundles of muscle fibers

Are supplies with a rich network of blood vessels and nerves

62
Q

Muscle (structure)

A

A bunch of fascicles rapped together

63
Q

Structure ct muscle big to small

A

Epimysium - dense fibrous ct that surrounds out side of muscle
Aka fascia

Perimysium - surrounds individual muscle fascicles

Endomysium surround individual muscle cells
Loose areolar ct

All are continuous with each other and come together at ends to form tendons ( muscle to bone )

64
Q

Muscle cell structure from big to small

A

Deep to endymsium
Is sarcolemma : cell membrane
Sarcoplasm : cytosol which contains large amounts of glycogen and myoglobin (red pigment that stores o2 like hemoglobin)

Myofibril (rod like protien structure that takes up most space) 80%
Can contain hundreds and thousends

Each myofibril is made up of myofilaments : protien molecules

And each myofilaments can be divided into a sarcomere : contractile unit

65
Q

Myofilaments

A

Make up myofibrils

Forms striation due to regular organization and pattern

66
Q

A band

A

Dark area
A in “dark”
Anisotropic

Where there is thick filaments and thin filaments

67
Q

I band

A

Light segments
I in light
Isotropic

Where there is only thin filaments

68
Q

Z line/ disco

A

Are the deviations between sarcomeres

Sarcomeres are connected z disk to z disk and connect form one end of muscle to the other

Composed of alpha actinin which lets thin filaments attach

69
Q

H zone

A

Found I. The middle of a band (light zone usually center of sarcomere)

Is only thick filaments

70
Q

M line

A

Dark line i between h zone that is in the middle of the a band

Composed of myomesin that holds myosin in place

71
Q

Thick filaments

A

Are made up of myosin

72
Q

Thin filaments

A

Made up of actin

73
Q

G actin

F actin

A

F actin - 2 strings of g actin wound together in helix

G actin individual actin molecule contains binding site. (Pearls)

74
Q

Tropomyosin

A

Is a long string like polypeptide that runs along the f actin
Hides or exposes binding site on g actin

Long enough to cover the active sites of 7 g actin

75
Q

Troponin

A

Contain 3 globular proteins
Troponin I
Troponin T
Troponin C

There is one troponin for ever tropomyosin stand

76
Q

Troponin I

A

Binds to actin

77
Q

Troponin T

A

Bonds to tropomyosin

And helps position troponin on f actin

78
Q

Troponin c

A

Binds calcium ions

What calcium binds to it it causes confirmation all shift of entire complex that results in exposure of myosin binding sites

79
Q

Myosin

A

Thick filaments

Made up 300 myosin
And each myosin is made up of 6 protien subunits
2 heavy Chains and 4 light chains
Heavy chains look like golf club which is where head attaches

Half of heads point up half down

Center is only heavy chains

80
Q

Hinge region

A

Is the connection between the head and shaft of myosin

Can bend
Creates the power stroke in muscle contraction

81
Q

Myosin head

A

Has an ATPase that binds and hydrolysis atp into adp

Atp provides energy for contraction

Each head is associated with 2 tails

Each thick filaments can interact with 6 thin filaments Bc head every 60 degrees

Every thin can go with 3 think
This means there are two thin for every thick

👍heads can bind to active sites on g protien molecules and form bridge

The heads are attached to rod like portion of heavy myosin

The heads have ATPase which lets the break down atp allowing it to bend and detach the myosin from the actin

82
Q

Cross bridges

A

The myosin heads link to the thin filaments that cause the the myofilaments to slide over each other

Results in shortening of sacromere

83
Q

Titin

A

Is super long name (biggest protien in human body)
Extends from z disc to m line

Forms core of thick myofilaments

Holds them in place and keeps the a band structured

Can stretch and recoil
Prevents over stretching and damage

Returns muscle to normal Length

Responsible for elasticity

84
Q

Dystrophin

A

Located between the sarcolema and outermost filaments

Acts like an integral membrane protien and connects links the muscle cell to the endomycium

May cause MD muscular distrophy
And affects boys

Most become wheel chair bond by 12

And die due to breathing difficulty by age 20

85
Q

T tubules

A

Invaginations
They communicate extra cellular space and are fille by extracellular fluid

They are located where the a and I band overlap

Flanked on either side by the sarcoplasmic reticulum

86
Q

Sr sarcoplamic reticulum

A

Elaborate network of smooth endoplamic reticulum that surrounds and encases each myofibril

It store calcium
Which can be released when action potential is conducted along the sarcolema

Runs parallel with myofibrils

However there are enlargements at the a band I band junctions aka terminal cisternae

87
Q

Triad

A

One t tubule with two terminal cisternas on both sides

Critical in muscle function

Contains large amounts of voltage dependent protiens calles dihydropirdine (DHP)channels or L type channels

88
Q

DHP and l type channels

A

Although called channels they do not allow calcium to move through but rather they are linked to calcium channels called (cells RyR) Ryanodine receptor channels

When membrane depolarizers the DHP detects signal which opens RYR releasing ca terminal cisternae to sr

89
Q

Neuromuscular junction😩👍😢

A

8 steps and they all suck

90
Q

Sliding filament model

A

The muscle contraction and shortening occur when myofilaments grip each other slide past each other and shorten sarcomeres

The proteins don’t shorten

Both Hzone and I band appear to be shrinking and A band doesn’t appear to shrink

91
Q

Neuromuscular junction step 1

A

Action potential arrives at axon terminal

(Skeletal muscle no stimulation by neuron means no contraction)

The axon delivers signal to neuro muscular junction (synapse)

92
Q

Neuromuscular junction step 2

A

The arrival of the actionpotential at the termial stimulates ca2+ ion voltage gated channels to open

Ca2+ moves into cell from outside the cell

93
Q

Neuromuscular junction step 3

A

The axon terminal contains synaptic vesicles fellow with the neurotransmitter acetylcholine ACh

Increased levels of Ca2+ triggers exocytosis and it releases ACh into cleft

94
Q

Neuromuscular junction 4

A

ACh diffuses across the synapse binding to the acetylcholine receptor
On the ligand gated ion channels (nicotinic type 1) in the sarcolema of the post synaptic tissue aka the motor end plate ( location of ACh receptors)

95
Q

Neuromuscular junction step 5

A

ACh binding causes ligand gated NA K channels to open these channels are more permeable to NA so it depolarizers the sarcolema

Which then causes the voltage gated NA channels to open initiating an action potential that spreads out from neuromuscular junction

Travels down sarcolema but also down t tubules
(Filled with extracellular fluid so high NA but low K)

ACh receptors or ligand channels allow NA into the cell activating voltage gated channels
Generation and propagating action potential

96
Q

Neuromuscular junction step 5a

A

Meanwhile for the muscle to relax
ACh is removed for binding site
Via an enzyme called acetylcholinesterase.
Which splits ACh into two components acetyl and choline which diffuse out of cleft

Choline which is essential nutrient. In vitamin B group (b4) is taken up by the axon terminal where it is recycled

Our bodies can produce choline but we also need to eat it to have enough

97
Q

Neuromuscular junction step 6

A

The action potential does its thing 😉

98
Q

Neuromuscular junction step 7

A

Action potentials spread across sarcolema and t tubules

The change in potential causes other voltage gated channels in t tubule to respond

Dihydropyridine
DHP

Or

L type gated channels which are mechanically linked to ryadine receptor channels (RyR)

Which are calcium channels located I the SR membrane

These two protein channels spans the distance t tubule and terminal cisternae

In response to change in potential the Ltype or DHP cause the RYR to open letting ca ions go from the sr and diffuse into sarcoplasm

These calcium ions bind to troponin causing it to move the tropomyosin molecules exposing the active sites on the g actin

99
Q

Neuromuscular junction step 8

A

When active sites are exposed it allows the formation of cross bridges

In resting state myosin head is cocked
And ready to go (it has adp and phosphate attached to it) the binding of actin causes the phosphate to detach from myosin head. Resulting in the release of energy which causes the myosin head to bend aka power stroke which forcefully pulls the actin past the myosin

Although half point one direction and the other half the other, they all pull myosin toward the middle (shorten sarcomere)

100
Q

Step 9 of neuromuscular junction

A

In order for significant shortening to occur

Head must detach
And reattach on new site

Head binds with atp molecule which detaches the head

ATPase rehydrolizes the atp into adp and p and causes the head to recock (the recovery stroke) preparing it for the next power stroke

During one muscle contraction this bridge cycle happens many times

101
Q

Cross bridge cycling

A

The attachment and reattcent of myosin heads and actin

Happens asynchronously meaning not all at the same time and all heads will be at different stages

Phase 1 power stroke or working stroke where myosin heads bend and retract the actin molecules

Phase 2 the recovery stroke :
Where the myosin heads detach from actin and are cocked back into high energy position the prepare for next stroke

102
Q

Relaxation of muscle

A

Begins when ACh is no longer being released
The ACh that is in the synapse is breaker down by acetylcholinesterase
Ending the action potential which stops the flow of ca out of the SR which allows the tropomine and tropomyosin complex to relAx blocking the active sites which prevents the cross bride cycle

103
Q

Muscle contracture

A

Occurs when muscle shortens and resists relaxing

Long term / permanent contractons Causes include (prolonged immobilization) spasticity(spasm) and muscle weakness

Temporay (rare) causes include servers muscle fatigue, resulting In physiologic contacture. Extreme exercise may lead to depleted atp which prevents the myosin head from detaching and muscle stays rigid

104
Q

Rigor Mortis

A

Is also caused by lack of atp when body dies

Death

It may take hour to fully develop

Breakdown of SR and leakage of ca which initiates cross bridge formation how ever because there is no atp the heads don’t unbind and muscles become rigid

105
Q

Muscle cramps

A

We don’t know

Contráctures are electrically silent or in other words we don’t see repeated action potentials coming down the motor neurons.
It occurs because of a physiological change in the fiber itself and not the motor neuron

Cramps are associated with many action potentials
Most commonly found in the leg and foot
Poorly understood

106
Q

Motor units

A

Motor neurons that are connected with skeletal muscle are called alpha motor neurons

It divides into several branches

Each innervating a muscle fiber

One alpha neuron and all the fibers it innervates is known as a motor unit

The size of motor units varies

In muscle involved in fine movement there are about 3 to 5 muscle fiber per neurons ex eye and hands

Muscles involved in powerful but less coordinated movemts have large motor units with thousands of muscle cells per neuron
Legs and back

107
Q

Muscle twitch

A

The contraction caused by a single action potential

The latent period - lag phase, is short 1-2 msec from when action potential reaches muscle until tension can be observed which is the time it takes fo ca to diffuse out of the sr and bind with tropomine moving the tropomyosin which allows for bridge formations to occure

Contraction phase is period of time when the muscle is generating tension and is associated with the cycling of bridges

Relaxation phase the time when muscle moves back to normal length

Muscle units randomly fire creating smooth action potentials because they are not all going at the same time

Even at rest some muscle fibers randomly fire

108
Q

Muscle tone

A

Due to muscle twitch firing even when muscle is relaxed causing the muscles to never completely relax even when asleep

Takes up slack
Deters atrophy

109
Q

Flaccid paralysis

A

When neuron to motor unit is cut and there is no electrical impulse to muscles causing them to become flaccid

110
Q

Isometric contrarion

A

When tension of the muscle increases without a corresponding Chang of length

Important for maintains posture

111
Q

Isotonic contraction

A

Is when tension stays relatively the same and length changes

Can be classified into

Concentric

Eccentric concentration

112
Q

Concentric

A

Isotonic
If muscle generates tension and entire muscle shortens

Curling a weight your bicep would be concentric contraction

113
Q

Eccentric contraction

A

ISOtonic

When muscle is generating force but muscle is lengthening

Works to decelerate the movement of the joint

Can generate more force then concentric contraction.

Better to train both

Essentric can cause more tearing resulting in more soreness

114
Q

Muscle size and muscle growth

A

Muscle size is determined by the number and size of myofibrils which is also determined by the amount of myofilaments

Resistance training causes an increase in myofilament protien production

Caused by small microtares on the micro filament level

It also causes there to be more connective tissue

Endurance trading does little for muscle size but helps increase its ability to produce atp aerobically

115
Q

How to generate more forever in contraction

A

More motor units are recruited

We are only able to use about 1/3 of our motor units

As fiber is fatigued they are replaced by other groups to allow for a longer contraction time

Only in rare circumstances can we use more motor groups which allows us to lift cars off of children

116
Q

Wave summation and tetanus

A

There is not refractory period so it can be re stimulated at any time meaning you can restimulate the same neuron with higher frequencies you would observe a gradual increase in force

It would get to a point where it becomes so high that it doesn’t have enough time to relax which would cause tetanus

Not enough time to remove calcium form charol creating maximum force

117
Q

Length tension relationships

A

If starting length is short the muscle has less room to contract making it a very weak contraction

Or if it stretched to the point where actin can’t touch myosin then less force will be generated

The best place is to allow every head to contract and contact actin and the sarcomere has the greatest distance to shorten

118
Q

Energy source of muscle contration

A

Ultimate source is atp

Cytosolic atp

Creatine phosphatE

Glycolysis

Aerobic or oxidative respiration

119
Q

Cytosolic atp

A

Floating pool of atp

Present in cytoplasm

Atp doesn’t require o2 to produce

Immediate but short lived

Few seconds of maximal activity

Not good long term

Good for small like eye contraction

120
Q

Creatine phospate

A

Once cytosolic atp is gone

High energy compound

Rapidly transfer phosphate to adp creating atp fast

Without o2

Requires creatine kinase (located on m line of sarcomere)

Can replenish atp pool several times

Only gives 10 sec mor time

Very common supplement only good for very small very specific activities

121
Q

Glycolysis

A

Is the break down of glucose

Primary source from glycogen

Can happen without o2

Major source during anaerobic activity

Only can sustain about a minute

122
Q

Aerobic or oxidative respiration

A

Metabolic mechanism in the mitochondria

Produces a lot more atp

Lasts much longer then a minute

Needs o2

Slower

No fast for intense

Moderate works 👍

Nutrient of choice is fatty acids

123
Q

Muscle fatigue

A

When the muscle is no longer able to contract optimally

124
Q

Central fatigue

A

The uncomfortable feeling you get when working out

Psychological fatigue

Factors realice to signal the brain that it’s tired

Occurs well before the muscle can no longer contract

125
Q

Peripheral fatigue

A

Can occur anywhere between the neuromuscular junction

Low frequency
: marathon running
Impaired ca release due to excitation coupling contraction problems
Recovery 24 to 72 hours

High-frequency 
Circuit training 
Impaired membrane excitability 
As a result from imbalance of ions 
Causes inadequate NA k pump inactivation NA channels and impairment of ca channels
Quick recover about 30 min

Other possible factors include

Accumulation of inorganic phosphates
To much hydrogen ion and ph change
Glycogen depletion
Imbalances in k

Not on the list is lactic acid it does not cause fatigue or muscle soreness

126
Q

Slow twitch

Oxidative type I

A 
Myosin ATPase activity slow
Size small
Duration of contraction long
Serca pump activity slow 
Fatigue resistant
Energy utilization aerobic/oxidative 
Capillary density: high
Mitochondria: high numbers
Color: red (contain myoglobin)
127
Q

Fast twitch oxidative type llA

A 
Myosin ATPase activity fast
Size medium
Duration of contraction short
Serca pump activity fast
Fatigue resistant 
Energy utilization both
Capillary density medium
Mitochondria medium numbers
Color red contains myoglobin
128
Q

Fast twitch glycolytic tips IIX

A 
Myosin ATPase activity fast
Size large 
Duration of contraction short
Serca pump activity fast
Fatigue easily fatigued
Energy utilization: anaerobic glycolytic
Capillary density low
Mitochondria low numbers
Color - white no myogloben
129
Q

Slow v fAst fibers

A

Slow twitch (ex deep calf) - good for standing

Fast twitch(eye muscles)- good for sprinting

Most muscles contain both

Women seem to have higher ratio of slow twitch to fast twitch

Default is type 1

Small neurons induce slow type

Large myelinated fibers induce fast type

Frequency of firing rates can also change type

Generally genetics plays biggest role in type of fiber

Training may be able to slightly alter ratios

130
Q

Agonist

A

A drug that has the same effect as a neurotransmitter

131
Q

Antagonist

A

Drug that blocks the effect of neurotransmitter

132
Q 
Neuromuscular blocker (drug)
😀
A

Ex tubcurarine ( comes from South America plant used for arrow poison) Alpha bungarotoxin (snake poison) pancuronium (lethal injection drug)

Acetylcholine receptor antagonists

Result flaccid paralysis

133
Q

Neuromuscular blocker(drug)🙃

A

Ex succinylcholine (a synthesized chemical known as the perfect poison for murder)

Acetylcholine receptor antagonist (initial depolarization but then blocks receptor)

Flaccid paralysis

134
Q

Neuromuscular junction drug 🥸

A

Neostigmine (synthesized chemical)

Inhibits acetylcholinesterase activity

Spastic paralysis

135
Q

Contractility 💪🏻 (drug)

A

Salbutamol (synthesized chemical aka albuterol)

Enhances serca pump Activity

Reduced contráctility

136
Q

Contráctility 👌

A

Caffeine (chemical found in seeds and nuts or leaves used as un insecticide by the plants)

Enhances ca release at SR

Increased contráctility

137
Q

Neuromuscular junction 🥴

A

Botulism

Blocks snare protiens

Flaccid paralysis

138
Q

Neuromuscular junction 🕷

A

Latrotoxin (black widow spider poison)

Snare protien agonist

Spastic paralysis

Anatomy (7 decks)

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