Muscles Flashcards
What is autonomic
involuntary
What is orb
Sphere
What is skeletal muscle
Muscle surrounding bones
What are myocytes reffered to as
Muscle fibres
What is the dark purple in the cell
Nuclei
Is skeletal muscle vuluntary
Mostly
Does skeletal muscle have one nucleus
no
How long are skeletal muscle cells
a few centimetres
What is striated
Bands of filaments
What is the difference between the appearance of skeletal and cardiac
Cardiac has intercollated discs
is cardiac muscle voluntary
no
Is smooth muscle striated
no
What is somatic
Voluntary
What is the function of muscle
Move bones, maintain posture, generate heat, protect visceral organs
Where does muscular energy come from
mitochondria
What is a muscle fasicles
group of fibers
What are muscle fibers
A skeletal muscle cell
Are muscles vascular
yes
What is the epi, peri and endomesium
Layers of the membranes in order of how far they go in
What is a epimesium
Fibrous connective tissue surrounding the entire muscle
What is the perimesium
Middle layer surrounding fasicles
What is the endomesium
Layer surrounding cells
What is direct muscle anchoring
Epimesium connected directly to bone/cartilage
What is indirect muscle connection
Uses tendons or aponeuroses to connect muscle to bones
what are tendons
Flexible but inelastic cord attaching muscle to bone
What is a fasicle arrangement’s
How the muscle is shaped
What is a circular fascicle
A Fasicle shaped like a circle, usually from the face named orb
What is convergent muscle
Fasicles converge to a single tendon
What is a parallel muscle fasicle
long muscles parallel to the long axis
What is unipennate bipennate and multipennate refer to
Number of muscle fassicles attachment
Where does the tendon lie in bipennate
Middle
What is a fusiform shape
thick in the middle but thin at the end
What are muscles named after sometimes
Location, size, orientation and shape, number of origins eg biceps triceps and quadriceps), location of attachments and muscle action
Why are origin and insertion not used
Origin isn’t always the embryological origin. Use attachments point instead
What are agonist and antagonist used for
To describe paried muscles
What does the agonist do
Provide a major force
What is the antagonist
Does the reverse of the major force
What are synergists
Muscles that aid the agonist
What are fixators
Stabilise by holding bones in place
DO tendons only attach to bone
no, they surround muscle, known as epimysium
How many nuclei do muscle fibers have
~250
What is a sarcomere
A little band of protein that is split by z lines. It is also what the myosin filament pulls
What is the sarcoplasmic reticulum
endoplasmic reticulum for muscles
What is sarcomeres mase of
I band is made of the actin attatchment, there is a myosin filament in the middle. Titin is at the other end
What is actin
Double helix structure of G actin. 1micron ling and 8nm wide. They scaffold to make the sarcomere smaller
How thick is myosin compared to actin
thick finament
What does myosin headn do
pull and contracts muscle
What is useful for muscle contraction
ATP and Ca 2+
What does contraction do
Cross bridges, pulling actin relative to the myosin
What is a sliding filament model
Myosin pulling the thin and thick filament to each other
What are muscle filaments on
Z line
What does relaxed state mean
Muscle has low resistance to stretch
What is a concentric contraction
Pulling contraction
What is a eccentric contraction
Pushing contraction
What is isometric contraction
Keeps length the same
What is active tension
Myosin pulls through the filaments and contracts them using atp
What is the length tension curve
The stretchiness of tension
What is the goldilocks zone for length and maximal tension
Middle lenggth 1.8 - 2.2 microns
What is in the goldilocks zone for maximal tension
Resting position
Why is there a goldilocks zone
goldilocks is where all the myosin heads attach
what connects myosin to the sarcomeres
titins
Is there a direct relationship between max force and velocity
no inverse
What is the power of muscle
force multiplied by velocity
Where do muscles use the most power
intermediate load and intermediate velocities
Do muscles push
NO
What is brachii
of the arm
What is carpi
bones of the wrist
what is pollicis
of the thumb
what is supra
over
What is surae
of the calf
what is teres
round
what is hamm
hollow or bend of the knee
what is the extensor digitorus
extend the digit of the fingers
what is a lateral pterygoid
portrudes the jaw (more chad)
What is the temporalis
Retracts the jaw (less chad)
What does the trapezius do
elevates and depresses the shoulder
What is the rectus abdominus
spinal flexion
What is the erector spinae
spinal extension
What is thesuprastanius
abduction
what is the latissimus dorsi
adduction
What is the deltoid
HEIL HITLER (FLEXION) of shoulder
What does triceps do
extendion of elbow
What does latissimus dorsi + deltoids also do
extension and hyperextension of shoulder
What does biceps brachii do
flexes the elbow joint
What does the pronator teres do
Pronates the hand
What does the supinator do
Supinates the hand
What extends the wrist
extensor carpi radialis and extension carpi ulnaris
What is the flexion wrist muscles
flexor carpi radialis and flexor carpi ulnaris
What flexes the fingers
flexor digitorum superficalus
What extends the fingers
extensor digitorum
What is the thenar eminence
the thumb muscles
What flexes the thumb
flexor pollicus longus
What extends the thumb
extensor pollicis longus
What adducts the thumb
adductor pollicus
what abducts the thumb
abductor pollicis
what is iliopsoas
hip muscles that flexion
What extends the hips
gluteus maximus
What does the gluteus medius do
abduction
What is the trecanter
attatchment point of the femur
what are the hip adducters
adduct the hips
what flexes the knee joint
hamstrings
What extends the knee joints
quadriceps femoris
What dorsiflexes the foot
digitorum longus
what plantarflexes the foot
Triceps surae
What does eversion of the foot
fibularis longus
what does inversion
tibialis anterior
Why os calcium important
calcium injection causes contraction, calcium deprivation prevents contraction
What is required to tense muscles and relav muscles
atp
What are the calcium pumps
PMCA and NCX
what does PMCA do
gets rid of calcium through atp
What is NCX
NaCa exchanger, lets ca in
What is the sarcoplasmic reticulum
giant endoplasmic reticulum which stores muscles
What is the sarcoplasmic/endoplasmic reticulum calcium pump
sarcoplasmic reticulum atpase, gets in and out of the SR
What is the SR
smooth endoplasmic reticulum network around each myofibril
What is calesquestrin
binds free calcium, lowering the concentration gradient, allowing the SR to store high calcium concentrations
Where does the extra calcium go
mostly SR but some in ECF
What is calcium released through
Digydropyridine receptor and ryanodine receptor
What is the dihydropyridine receptor
plasma membrane calcium channel and is voltage gated, they are really slow channels (L type)
What is the ryanodine receptor
sarcoplasmic reticulum with no voltage gate, they are mechanically gated
What is pushing the ryamodine receptor when opened
dihydropyridine receptor
How close are digydropyridine receptors and rymadine receptors
very
What is a t tuble
little bit of ECF that goes in
What blocks the actin myosin binding site
tropomyosin
What is troponin c
binds calcium
what binds the tropinin out of the way for myosin to latch
calcium
What is the neuronmuscular junction
nicotinic are ligand gated Na channels, motor neurons secrete acetylcholine when stimulated
What is the acetocholine receptors
they open up the sodium channels
What happens to the action potential
goes to the t tubles
where does the calcium go
into the sr which allows the muscle to contract
How soes contraction stops
motorneuron stops, acetylcholine degrades, calcium gates close and escape, it is called contraction
what is the whole cycle calles
twitch
how long is the twitch compared to the action potential
long compared to AT, and there is a latent period
What is wave summation
lots of action potentials releasing more calcium
what is titanic tension
max amoutn of tension
What is a golgi tendon organ
It figures out tension level of muscles, so figures out proprioception for us
What do muscle spindles look like
They are stretch receptors in the golgi tendon organ
How many neuromusclar junctions do nmjs have
2
What is a gto inverse myotactic reflex
the inverse muscle reflex, turns off the alpha neuron, sensory neuron inhibits an inhibitory reflex
What is the tibialus anterior
big toe lifts up
What does number of myofibers mean
strength
what does number of MU’s mean
Precision
What re the types of muscle fibers
slow, fast fatiguable, and fast fatigue resistant (medium)
what are the fast fatigue resistant vs fast difference
Fast fatigue has mitochondria, fast fatigue resistant has no mitochondria
What is the type ii muscle
fast
What is the small muscle
Slow twitch
What has the highest myosin atpase activity
Fast twitch
What msucles are oxidated
red (slow twitch muscles)
What muscles are activated first
slow twitch
What is the shape of smooth muscle
spindle when elongated
What is a weak muscle compared to the other muscles
Smooth
What type of muscle is multinuclear
skeletal
What causes the heart to beat
the heart, meaningg it is autonomc
What is contained in both cardiac and skeletal muscles
myofibrils
What is the dolution of cardiac muscles being one cell, not fibers
there is gap junctions that pass through cells
What causes cardiac muscle to contract
Itself, it makes its own action potential
What is a desmosome
transfers force
What is special about pacemakers
it leaks sodium, causing action potentials
What is calcium used in cardiac muscle
to depolarise
what is a funny channels
They depolarise the heart with sodium by leaking sodium
What is the cottom of the heart called
the apex
where does the heart squeese first
the bottom (APEX)
How long does the refactory period lasts
250ms
What part of the heart depolarises
the sinoatrial node
what causes the atrium to contract
the SA node
What is a P wave
the atrium depolarisation
What is the ventricular polarisation
the QRS complx
what is the t wave
Ventricular repolarisation
What does contracted smooth muscle look like
blob
Where does the calsium come from
the matrix
are the t tubles in smooth muscle
no
how long can smooth muscles last
for your entire lifetime
What regulates smooth myosin
phosphate and calcium
What activates calcium channels in smooth muscles
temp, co2, O2, NO, PH, stretch, pacemakers and autonomic nervous system activity
are there strech activated gates in smooth muscle
yes
What does myosin pull in smooth muscle
everywhere
how long is the latent period in smooth muscle
0.075 sec
how long does tension peak
0.5 sec
