9. Musculatory System I Flashcards
Formative immature cells of muscles; present in fetal stage; func: mitosis
Myoblasts
Non striated
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 ct 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 or 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 lIght 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 sacks 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 ca+ion in ECF
Na+
Most numerous ca+ion 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 NEGATIVE
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
Ach
It is a neurotransmitter or a chemical messenger (LIGAND)
Acetylcholine
Part of the NMJ where Ach binds
Nicotinic receptors or “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 _ (kasi katabi sya ng T tubules) 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
Most important substance for muscular contraction
Calcium
BEQ: “Cross bridging”
- troponin
- tropomyosin
- myosin
- actin
Tropomyosin
Myosin head will attach to actin known as
Cross bridging
ATP in the myosin head is broken down by (what enzyme) into _____
Atp /ATPase/ = ADP+P
Immediate source of energy
ADP+Phosphate
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 a state of RIGIDITY due to Cross bridging
(Lysosymes digests 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 important 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 theres accumulation of lactic ACID
Blood becomes ACIDIC
⬆️H ⬇️pH = ACIDIC
Hco3- + H =
H2O
CO2
⬆️ CO2
⬇️ O2
What is the response of the body?
Hyperventilation
Other names for aerobic glycolysis (4)
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
O2
Pyruvate
Amino acids
Fatty acids
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 ends 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 (mlck)
Blocks myosin from binding to actin in skeletal and cardiac muscle
Tropomyosin
Beq: binding site of Calcium in MUSCLE (only)
Troponin
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 or 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
Cervical Mandibular Temporal Zygomatic Buccal
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
Buccinator
Nerves anesthetize 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 VII (7 singkit)
Moves eyebrows inferiorly; wrinkles forehead
FROWNING 😞
Corrugator supercilii
Moves eyeballs inferiorly and laterally
Superior oblique
Moves eyeballs superiorly and laterally
Inferior oblique
Elevates eyelids = eye opening
Levator palpebrae superioris
What innervates levator palpebrae superioris
CN III :3
Mneumonic for innervation of extrinsic muscles of the eye
SO4 LR6 R3
Innervation for superior oblique
CN4 trochlear nerve
Innervation of lateral rectus
Cn6 abducens
Moves eyeballs laterally
Lateral rectus
Moves eyeballs superiorly
Superior rectus
Moves eyeballs inferiorly
Inferior rectus
Moves eyeballs medially
Medial rectus
CN III V1
Opthalmic branch
CN III V2
Maxillary branch
CN III V3
Mandibular branch
Muscles of mastication (mneumonic)
TIME
Only muscle that retracts the mandible
Temporalis
Only muscle that depresses the mandible (open)
Lateral or external pterygoid
