7. Musculatory System Flashcards
Formative immature cells of muscle; present in fetal stage; func: Mitosis
Myoblast
Nonstriated
Involuntary
Can divide
Smooth muscle
Spindle-shaped muscle tissue
Smooth muscle
Only mature muscle tissue that can divide
Smooth muscle
Striated Voluntary Multinucleated Hypertrophy only Cannot multiply
Skeletal muscle
Location of nucleus of skeletal muscle
Lateral surface
Striated
Involuntary
Cannot multiply;
Hypertrophy only
Cardiac muscle
What type of muscle cell or tissue is the Heart
Cardiac muscle
What connects cardiac muscle cells together
Intercalated discs
Cellular junctions in cardiac muscles
Desmosomes
Gap junctions
Outermost connective tissue layer that covers MUSCLE BELLY
Epimysium
Middle layer covers FASCICLES
Perimysium
Innermost; covers muscle cells or fibers
Endomysium
Connects muscle to bone
Tendon
Connects bone to bone
Ligaments
Group of muscle fibers covered by perimysium
Fascicle
Cell membrane or plasma membrane of muscles made up of phospholipid bilayer
Sarcolemma
Structures that makes up the muscle cell or fiber
Myofibrils
Structures that makes up myofibrils
Myofilaments
2 kinds of Myofilaments
Thin filaments
Thick filaments
Thin filaments is composed of what protein
Actin
Thick filaments are composed of what protein
Myosin
Shape of myosin
Golf club 🏑
Functional/contractile unit of muscle; from Z disc to another Z disc
Sarcomere
🔹Separates one sarcomere to another.
🔹Attachment for thin filaments.
🔹Passes in the middle of the I band
Z discs
Contains thick but no thin filaments (MYOSIN ONLY)
H zone
Passes in the middle of H zone
M line
aka dArk band
A band
aka l”i”ght band
I band
Blocks the myosin binding sites in actin (relax muscle)
Tropomyosin
🔹Holds the tropomyosin in place.
🔹Binding site for Ca ions to allow movt of tropomyosin.
Troponin
Perpendicular sarcolemma
Transverse tubules or T tubules
Endoplasmic reticulum of muscle fiber
Sarcoplasmic reticulum
Storage for calcium
Sarcoplasmic reticulum
Most impt substance for muscular contraction
Calcium
Dilated end sac of sarcoplasmic reticulum
Terminal cisterns
Cytoplasm of a muscle fiber
Sarcoplasm
Stored chains of glucose
Glycogen
Glycogen is mainly stored in
✔️Liver
✔️Skeletal muscle
✔️Adipocytes
Process: glycogen to glucose
Glycogenolysis
Maximum storage of glycogen
2 lbs
Process: glucose to glycogen
Glycogenesis
When does the body produce glycogen
Hyperglycemic state
Hormone responsible for production of insulin (glycogen stored in insulin sensitive cells)
Beta cells of pancreas
🔹Protein that binds OXYGEN = red color of muscle.
🔹Counterpart of RBC (hemoglobin = red color)
Myoglobin
Largest protein of the body found in muscles
Titin
Total muscles in the body
650 muscles
Attachment for THICK filaments
M line
Overlapping thick and thin filaments
A band
Attachment of THIN filaments
Z line or disc
Filaments seen in light or I band
Thin filaments only
aka Theory of muscle contraction
Sliding filament mechanism
% of ICF
40% ICF
% of ECF
20%
What is the resting membrane potential? (mV)
-70mV (-90mV in Guyton)
Most numerous cation in ECF
Na+
Most numerous cation in ICF
K+
Charge inside the cell when it is in resting state or polarized state
Resting membrane potential
1st channel to open once there’s electrical current
Voltage-gated Na+ channels
Why is depolarization and repolarization happens? What process?
(Na goes IN, K goes OUT)
Because of simple diffusion
🔹Na+ influx = cell more + = ______
🔹Wherein, cell from negative to a positive state.
🔹Remove a cell in a polarized state(-)
Depolarization
Channels that are delayed to open (opens after action potential)
Voltage-gated K+ channels
K+ efflux(out) = cell goes back to resting state = ______
🔹Change charge of cell from (+) to (-)
Repolarization
What is the Threshold stimulus to generate an action potential
-55mV
Signal that has potential to trigger an axon
Action potential
Corrects position of Na+(out) and K+(in)
Sodium potassium pumps
Ratio in Na-K pumps
“2PISO3”
2 Potassium IN
3 Sodium OUT
In precontraction phase, an ACTION POTENTIAL from nerve fiber stimulates _____ to open
Voltage-gated calcium channels
Calcium influx causes release of _____ in the NMJ
Acetylcholine (Ach)
It is a neurotransmitter or a chemical messenger (LIGAND)
Acetylcholine
Part of the NMJ where Ach binds
Nicotinic receptors / “Ligand”-gated Na+ channels
Na+ enters muscle fiber (Depolarization) creating a ______
Muscle action potential
Muscle action potential travels to what part of the muscle cell
Sarcolemma and T tubules
Muscle action potential opens _____ which stores Calcium
Sarcoplasmic reticulum
Responsible in releasing calcium ions into the sarcoplasm
Sarcoplasmic reticulum
Where does calcium ions bind
Troponin
What happens when calcium binds to troponin
Troponin moves tropomyosin away from blocking the myosin heads sa actin binding sites
Myosin head will attach to actin known as
Cross bridging
ATP in the myosin head is broken down by (what enzym) into ______
ATP / ATPase = ADP + P
Immediate source of energy
ADP + Phospate
Source of energy
ATP
Occurs when actin moves towards the M line and ADP is released
Power stroke
Actin moves towards M line, Z discs moves towards each other, sarcomere shortens.
Muscle contraction
When does myosin detach from actin
When there is another ATP that binds to myosin head
Detachment of myosin to actin = sarcomere _______
Sarcomere goes back to original place
As long as there are high amounts of _____ and ______ in the sarcoplasm, contraction cycle continues
Ca+ and ATP
This moves calcium back to the sarcoplasmic reticulum
Ca+ active transport pumps
Enzyme that breaks down Ach after it binds to Nicotinic receptors
Acetylcholinesterase
Phenomenon seen in dead body. Muscles are in state of RIGIDITY due to cross bridging (Lysosymes digest SR causing release of Ca resulting to crossbridging but no ATP so myosin doesnt detach to actin = muscles remain contracted)
Rigor mortis
Causative agent or bacteria of botulinum toxin
Clostridium botulinum
Prevents release of Ach in the NMJ resulting to muscle paralysis or relaxation
Botulinum toxin
Poisonous plant; blocks NICOTINIC receptors (close: Ach cannot bind =cant stimulate muscle contraction) Resulting to Muscle paralysis
Curare
Drug derived from Curare
Pancuronium bromide
Drugs used in lethal injection
✔️Thiopental (sedative)
✔️Potassium chloride (to stop heart)
✔️Pancuronium bromide (from curare)
Other name of Succinylcholine
Suxamethonium
Succinylcholine is for
Laryngospasm
Binds to Ach receptors resulting to muscle paralysis.
Used in laryngospasm
Succinylcholine
Other name for creatine phosphate mechanism
Direct phosphorylation
Fuel for creatine phosphate mechanism
Creatine phosphate
End products of creatine phosphate mechanism
1 ATP
1 Creatinine
Other name for GLYCOLYSIS
Anaerobic respiration
Process of breaking down glucose
Glycolysis
Fuel for glycolysis
Glucose
End products of glycolysis
2 ATP
2 Pyruvate
🔹Subpathway of glycolysis.
🔹Glucose to Lactic Acid.
🔹Happens if there is insufficient oxygen.
🔹Example during heavy exercises.
Anaerobic glycolysis
End product of anaerobic glycolysis
Lactic acid
Muscle pain is caused by accumulation of
Lactic acid
pH of blood and average
7.35-7.45 (7.4)
Most impt buffer that prevents sudden change in pH in the blood
Bicarbonate HCO3-
Blood is what pH
Slightly basic
What happens to pH of blood if there’s accumulation of lactic acid
Blood becomes acidic
⬆️H ⬇️pH = acidic
HCO3- + H =
H2O
CO2
⬆️CO2 ⬇️O2
What is the response of the body?
Hyperventilation
4 other names for Aerobic Glycolysis
🔹Aerobic respiration
🔹Krebs cycle
🔹Citric acid cycle
🔹Tricarboxylic acid cycle
Happens when there is enough oxygen in the body
Aerobic glycolysis
Fuel for Aerobic glycolysis
✔️Fatty acids
✔️Amino acids
✔️Oxygen
✔️Pyruvate
End products of Aerobic glycolysis
36-38 ATP
H2O
CO2
Glycolysis and Creatine phosphate mechanism happens in what part of the cell?
Cytoplasm
Kreb cycle happens in what part of the cell?
Mitochondria
Type of skeletal muscle fiber that produces SLOW and WEAK contractions but is RESISTANT to FATIGUE
Slow oxidative fibers or RED muscle fibers
Postural muscles are examples of what type of skeletal muscle fibers
Red muscle fibers
Responsible for the red pigment of the muscle fibers and also carries oxygen
Myoglobin
Red muscle fibers undergoes what type of glycolysis
Aerobic glycolysis (⬆️ATP)
Produces fast and strong contractions but NOT RESISTANT to fatigue
Fast glycolytic fibers
White muscle fibers
White muscle fibers undergoes what type of glycolysis
Anaerobic glycolysis (⬇️myoglobin, ⬇️O2)
Connects end of cardiac muscle to one another
Intercalated discs
Which muscle has the most numerous mitochondria to allow continuous contraction (⬆️kreb, ⬆️ATP)
Heart or CARDIAC muscle
What 2 cellular junctions found between cardiac muscle cells
🔹Gap junctions
🔹Desmosomes
Shape of smooth muscle tissue
Spindle-shaped
For binding of Calcium in smooth muscle tissue
Calmodulin
For binding Calcium in Skeletal and Cardiac muscle
Troponin
Blocks myosin from binding to actin in Smooth muscle
Myosin light chain kinase
Blocks myosin from binding to actin in skeletal and cardiac muscle
Tropomyosin
Scalp muscles are innervated by what nerve
CN VII Facial nerve
Moves scalp posteriorly
Occipitalis
Moves scalp anteriorly
Frontalis
Raises eyebrow; SURPRISE
Frontalis
🔹Aponeurosis in the head
🔹connects occipitalis and frontalis
Galea aponeurotica
Muscle to muscle attachment
Aponeurosis
Mouth muscles are innervated by what nerve
CN VII Facial nerve
Closes lips
Kissing
Pouting(major)
Orbicularis oris
Elevates upper lip
Zygomaticus major Zygomaticus minor Lev anguli oris Lev labii superioris ala que nasi Lev labii superioris
Caninus muscle
Levator anguli oris
🔹Longest name
🔹Elevates upper lip and ala of nose
Levator labii superioris ala que nasi
Depresses lower lip
Depressor labii inferioris
Depresses angle of mouth
Depressor anguli oris
Other names of Buccinator (3)
Cheek muscle
Kissing muscle
Trumpeter’s muscle
🔹Presses cheeks
🔹whistling, blowing, sucking, kissing
🔹keeps food away from vestibular area
Buccinator
Moves angle of mouth laterally.
Fake/sardonic smile; Grimace
Risorius
Protrudes lower lip; pouting
Mentalis
🔹Neck muscle
🔹depresses lower lip and mandible
🔹major muscle for Grimace
Platysma
Angle of mouth where 8 muscles meet
Modiolus muscle
Mneumonic for modiolus muscles
“LLORDD BuZy”
Lev anguli oris Lev labii superioris Orbicularis oris Risorius Dep anguli oris Dep labii inferioris Buccinator Zygo major
5 branches of CN V or Facial nerve
Mnemonic: The Zebra Bump My Car
Temporal n. Zygomatic n. Buccal n. Mandibular n. Cervical n.
Muscle penetrated in classic mandiblock
Buccinator
Where to deposit in mandiblock
Pterygomandibular space
Why contralateral side in doing Mandiblock
To avoid parotid = Bell’s palsy
Muscles that comprises the pterygomandibular raphe
✔️Superior pharyngeal constrictor m.
✔️Buccinator
Nerves anesthesize in classic mandiblock
✔️IAN
✔️Lingual nerve
What muscle to incise to drain abscess on pterygomandibular space
Buccinator
Muscle that closes eyes
Orbicularis oculi
Nerve that innervates orbicularis oculi
CN 7
Moves eyebrows inferiorly; wrinkles forehead
FROWNING 😠
Corrugator supercilli
“Corrugator supersaiyan 😠”
Move eyeballs inferiorly and laterally
Superior oblique
Move eyeballs superiorly and laterally
Inferior oblique
Elevates eyelids = eye opening
Levator palpebrae superioris
What innervates levator palpabrae superioris
CN 3
Mnemonic for innervation of extrinsic muscles of the eye
SO4 LR6 R3 IO3
Innervation for superior oblique
CN 4 Trochlear nerve
Innervation of Lateral Rectus
CN 6 Abducens
Moves eyeball laterally
Lateral Rectus
Moves eyeball superiorly
Superior rectus
Moves eyeball inferiorly
Inferior rectus
Moves eyeball medially
Medial rectus
CN V1
Opthalmic branch
CN V2
Maxillary branch
CN V3
Mandibular branch
Muscles of mastication
“TIME”
Temporalis m.
Internal pterygoid m.(medial)
Masseter m.
External pterygoid m.(lateral)
Only muscle that retracts the mandible
Temporalis
Only muscle that depresses the mandible (open)
Lateral or external pterygoid
Muscles of mastication are innervated by
CN V3
Fan-shaped muscle
Temporalis
Temporalis O: I: A: -Anterior/Vertical fibers: -Posterior/Horizontal fibers:
Temporalis O: tempral bone I: coronoid process and ramus(Lat. side) A: -Ant/vertical fibers: elevates md -Post/horizontal fibers: retracts md
Only muscle that retracts the mandible
Posterior fibers of Temporalis
Muscles of mastication that elevates mandible
“TIM”
Temporarlis
Internal pterygoid
Masseter
Internal pterygoid is aka
Medial pterygoid
External pterygoid is aka
Lateral pterygoid
Internal/medial pterygoid
O:
I:
A:
Internal/medial pterygoid
O: medial surface of the lateral pterygoid plate of the sphenoid bone
I: ramus (medial side) and angle of md
A: elevates md and bennett movement
Masseter
O:
I:
A:
Masseter
O: maxilla and zygomatic arch
I: angle of md and ramus (Lateral)
A: elevates md
External/Lateral pterygoid
O:
I:
A: (3)
External/lateral pterygoid O: lateral surface of the lateral pterygoid plate of the sphenoid bone I: TMJ/Condyle A: -depresses md -bennett movt -protrudes md
Only muscle of mastication for mouth opening or depression of md
Lateral/external pterygoi
What is the major muscle for mouth opening
Anterior belly of digastric muscle
Anterior belly of digastric muscle is innervated by
CN V3
What innervates the posterior belly of digastric muscle
CN VII Facial nerve
Moves tongue inferiorly and anteriorly
Genioglossus
Genioglossus
O:
I:
A:
Genioglossus
O: genial tubercle
I: tongue
A: moves tongue inf and ant
Styloglossus OIA
Styloglossus
O: styloid process of temporal bone
I: tongue
A: moves tongue sup and post
Hyoglossus OIA
Hyoglossus
O: hyoid bone
I: tongue
A: moves tongue inferiorly
Extrinsic muscles are innervated by
✔️Genioglossus
✔️Styloglossus
✔️Hyoglossus
✔️Palatoglossus(except)
CN XII Hypoglossal nerve
What innervates Palatoglossus
Pharyngeal plexus (9/10/11)
ix - Glossopharyngeal
x - Vagus
xi - Accessory
Palatoglossus O: I: A: -tongue: -palate:
Palatoglossus O: soft palate I: tongue A: -moves tongue SUP. towards palate -moves palate INF. towards tongue
Intrinsic tongue muscles
“VITS”
Vertical m.
Inferior longitudinal
Transverse
Superior longitudinal
Intrinsic muscles of tongue OIA
Intrinsic muscles of tongue
O: tongue
I: tongue
A: changes SHAPE of tongue
Changes action of tongue
Extrinsic muscles of tongue
Changes shape of tongue
Intrinsic muscles of tongue (VITS)
Flattens and broadens tongue
Vertical
Shortens and thickens tongue (2)
Inf longitudinal
Sup longitudinal
Elongates and narrows tongue
Transverse
What innervates the intrinsic muscles of tongue (VITS)
CN XII Hypoglossal nerve
4 suprahyoid muscles
🔹Digastric muscle - ant and post belly
🔹Mylohyoid
🔹Stylohyoid
🔹Geniohyoid
Action of suprahyoid muscles (2)
Suprahyoid muscles depresses mandible and elevtaes hyoid
Muscle of floor of the mouth
Mylohyoid
Muscle that causes difficulty when taking radiograph on lower molars
Mylohyoid
What innervates the mylohyoid and anterior belly of digastric muscle
CN V3
What innervates the stylohyoid and post belly of digastruc m.
CN VII Facial nerve
Infrahyoid muscles
“TOSS
Thyrohyoid
Omohyoid
Sternohyoid
Sternothyroid
Action of all infrahyoid m.
Infrahyoid muscles depresses hyoid
Rotator cuff muscles
“SITS”
Supraspinatus
Infraspinatus
Teres MINOR
Subscapularis
Action of supraspinatus and sybscapularis
Medial rotation
Action of infraspinatus and teres MINOR
Lateral rotation
BQ: muscle used in pitching a baseball
Rotator cuff muscles
Hamstring muscles
(Hams3ngs - Bi Semi Semi)
Biceps femoris
Semimembranosus
Semitendinosus
Action of hamstring muscles
Flexes legs
“Running muscles”
Hamstring muscles
What innervates the hamstring muscles
Sciatic nerve
Longest nerve in the human body
Sciatic nerve
Longest/largest CRANIAL NERVE in the BODY
CN X Vagus
Longest/largest CRANIAL NERVE in the HEAD and NECK
CN V Trigeminal
Longest INTRACRANIAL nerve
CN IV Trochlear
Smallest or shortest cranial nerve
CN IV Trochlear
Quadriceps muscles
Rectus femoris
Vastus Lateralis
Vastus Intermedius
Vastus Medialis
“Sa RECTO may 3 VASTUS”
Most common muscle for IM injection
Vastus Lateralis
Muscles for IM injection
✔️Vastus Lateralis
✔️Gluteus maximus
✔️Deltoid
Safest part of Gluteus Maximus to inject to avoid sciatic nerve
Superolateral or upper outer corner
Degree of IM injection
90 degrees
Action of all quadriceps muscles
Extend legs
Flexes legs:
Extends legs:
Flexes legs: hamstrings (bi semi semi)
Extends legs: quadriceps (3 vastus sa recto)
Innervation of quadriceps muscles
Femoral nerve
Needle angulation: INTRADERMAL
0-15
choices: go for lowest value. 0 kung meron
Needle angulation: IV
35 degrees
Most common site for IV injection
Antecubital
Needle angulation: SUBCUTANEOUSLY
45 degrees
Most common drug injected subcutaneously
Insulin
Needle angulation: IM
90 degrees
Type of muscle adaption where there is healing fibrous scar tissue
Fibrosis
Enlargement of muscle fiber
Muscular hypertrophy
Type of enlargement of muscle fiber or muscle hypertrophy assoc with CONGESTIVE HEART FAILURE
Pathologic muscular hypertrophy
Type of enlargement of muscle hypertrophy assoc with patient exercising
Physiologic muscular hypertrophy
Increase in number or muscle fibers or cells
Muscular hyperplasia
Type of muscle cells that can undergo hyperplasia
Smooth muscles
“Muscle wasting”; loss of myofibrils
Muscle atrophy
Painfully twisted and tilted neck due to contraction of sternocleidomastoid
Torticollis
Other name for torticollis
Wry neck
Px with torticollis or wry neck: contraction of RIGHT sternocleidomastoid = chin goes to what side
Right SCM = Chin LEFT side
General term for muscle degeneration
Muscular dystrophy
It is the most common muscular dystrophy. It is a genetic disorder characterized by progressive muscle degeneration
Duchenne Muscular Dystrophy
Abnormal, random, spontaneous muscle contractions
Fibrillation
Pacemaker of heart
Sinoatrial node (SA node)
SA node is seen in the
Crista terminalis which is located in the SUPERIOR portion of RIGHT ATRIUM
Tx for fibrillation: administering a controlled electrical shock to restore nrmal rhythym
Defibrillation
Stop in effective blood flow due to FAILURE OF HEART TO CONTRACT effectively
Cardiac arrest
An example of cardiac arrest aka “flat line”
Asystole
Management for Asystole or flat line
CPR
Ration of compressions: breaths in CPR
30 compressions : 2 breaths
Compression rate
100 compressions per minute
