Ch 10 Flashcards
How many types of muscle is there?
Three:
Cardiac
Smooth
Skeletal
Cardiac Muscle
Only found in the heart
Short, branching fibers
appears striped
involuntary muscle - contracts automatically
Smooth Muscle
Found in digestive tract/blood vessels/bladder/airways/uterus
Does not appear striped when viewed under microscope
(nonstirated)
Know as involuntary - contracts automatically
Skeletal Muscle
Attached to bone and causes movement of body
Voluntary muscle - can be contracted at will
appears striated when looked at under microscope
Muscle Fiber
Skeletal muscle cell
Endomysium
Delicate connective tissue that covers each muscle fiber
Fascicles
Muscle fibers that are grouped in bundles
Perimysium
A sheath of tougher connective tissue that encases the fascicles
Epimysium
Another layer of connective tissue that surrounds the muscle as a whole and binds all the muscle fibers together
Fascia
Connective tissue that surround the muscle outside of the epimysium
Deep Fascia
Lies between muscles
Superficial Fascia
(hypodermis) resides just under the skin
Direct Attachment
Muscle fibers merge with the periosteum of the bone, forming a strong attachment
Indirect Attachment
The epimysium extends past the muscle as a tendon (a long fibrous cord). Then the tendon merges with the periosteum.
Aponeurosis
When muscle attaches to muscle. Epimysium extends past the muscle as a flat broad tendon then fuses with the cover of the other muscle. occasionally it will also attach to bone.
Sarcolemma
The plasma membrane surrounding each fiber
Sarcoplasm
The cytoplasm of the muscle cell
Myofibrils
Long protein bundles - they store glycogen (used for energy & oxygen)
Sarcoplasmic reticulum
Smooth endoplasmic reticulum of a muscle fiber - surrounds each myofibril.
(where calcium ions are stored)
Myofilaments
The even finer fibers inside of myofibrils
What are the two type of myofibrils?
Thick and Thin
That are thick myofillaments made out of?
The protein called actin
Transverse Tubules
System of tubules that extend across the sarcoplasm.
Thick filaments
shaped like a golf club
thin filaments
consists of two chains of actin. looks like string of beads.
entwined with two other proteins: Tropomyosin and Troponin
Sarcomeres
Section between z-disks, acts as a lattice work to form units
Z-disc or Z-line
Serves as anchor point for thin myofilaments
Motor Neuron
Skeletal muscle must be stimulated by a nerve to contract, this is the neuron that do that.
Axons
Extensions from the cell bodies, carries the impulses to the skeletal muscles
Neuromuscular Junction
Connection between motor neuron and a muscle fiber
Actin
Causes contaction in muscle
Myosin
Causes contraction in muscle
Synaptic Cleft
The narrow space between the end of the motor nerve and muscle fiber
Neuro Transmitter
Chemical Messenger
Acetylcholinesterase
The enzyme that breaks down any remaining ACh while calcium ions are pumped back into the sarcoplasmic reticulum.
Muscle Tone
Continuous state of partial contraction
Motor Unit
Threshold
Twitch
Treppe
Incomplete tetnus
Complete tetnus
Strong Stimulus
Weak Stimulus
Recruitment
Isotonic Contractions
Isometric Contractions
Origin
Refers to the end of the muscle that attaches to the more stationary bone
Belly
Thick midsection of the muscle
Insertion
The end of the muscle that attaches to the more movable bone
Hypertrophy
When the muscle enlarges, caused by weight training.
Atrophy
When lack of use happens, the muscle fibers/ muscles shrink
Frontalis
Raises eyebrows when glancing upward or when showing surprise
Orbicularis Oculi
A sphincter muscle that closes the eye when blinking or squinting
Zygomaticus
Draws the mouth upward when laughing
Orbicularis Oris
Closes the mouth and purses the lips like when kissing
Buccinatior
Assists in smiling and blowing as well as chewing
Temporalis
Aids in closing the jaw
Masseter
Closes the jaw
Sternocleidomastoid
Flexes the head, rotates the head to the opposite side when only one muscle contracts
Trapezius
Extends the head and flexes the head to one side. Also elevates the shoulder.
Maximus
Largest
Minimus
Smallest
Major
Large
Minor
SMall
Longus
Longest
Brevis
Shortest
Deltoid
Triangular
Rhomboid
Diamond shaped
Serratus
Sawtoothed
Trapezius
Trapezoidal
Pectorialis
Chest
Brachio-
Upper Arm
Radialis
Radius
Gluteus
Butt
Femoris
Femur
Sterno-
Sternum
Cleido-
Clavical
Mastoid
Mastoid Process
DIgiti
Finger or toe
Pollicis
Thumb
Biceps
Two origins
Triceps
Three origins
Quadriceps
Four origins
Rectus
Straight
Transverse
Across
Oblique
Diagonal
Adductor
Adducts
Abductor
Abducts
Flexor
Flexes
Extensor
Extends
Levator
Elevates
External Intercostals
Lie superficially between the ribs; elevate the ribs during inspiration
Internal Intercostals
Lie deeper than the external intercostals; depress the ribs during forced exhalation
Diaphragm
Enlarges the thorax to trigger inspiration
Rectus Abdominis
Flexes the lumbar region of the spinal column to cause bending forward at the waist. Extends from the sternum to the pubic bone.
Transversus Abdominis
Compresses the contents of the abdomen
External Oblique
Compresses the abdominal organs. Aids forceful expiration, vomiting, and deification. Also allows flexion of the vertebral column and rotation and lateral bending of the trunk.
Linea Alba
The white line
Where the muscles of the abdominal wall meet in the midline. Is a tough band of connective tissue
Transversus Abdominal
Compresses the contents of the abdomen
Internal Oblique
Stabilizes the spine and maintains posture, just like the external oblique muscles; also permits rotation of the waist
Deltoid
Abducts, flexes, and rotates the arm.
involved in swinging the arm (walking or bowling) also raises the arm to perform tasks such as writing on an elevated surface
Pectoral Major
Flexes and adducts the upper arm, such as climbing and hugging
Serratus Anterior
Drives all forward reaching and pushing movements. pulls the shoulder down and forward.
Trapezius
Raises and lowers the shoulders;
stabilizes the scapula during arm movements
Latissimus dorsi
adducts the humerus; extends the upper arm backward. serves to pull body upward when grasping an object overhead such as when climbing
Rotator Cuff
Supraspinatus
Infraspinatus
Teres Minor
Subscapularis
(SITS muscles)
Brachialis
The prime mover when flexing the forearm
Biceps Brachii
Assists the brachialis when flexing the forearm, also flexes the elbox and supinates the forearm (like opening a bottle with a corkscrew)
Triceps Brachii
The prime mover when extending the forearm
Brachioradialis
Helps the brachialis and the biceps brachii flex the forearm
Pronator muscles
allow the arm to pronate (palm down)
Supinator Muscle
Lies deep in the forearm near the elbow and joins forces with biceps brachii to allow supination (palms up)
Flexors
Muscles that flex the wrist
Extensors
Act to extend the wrist
Iliopsoas
Flexes the thigh. This refers to a combinations of the following muscles
Illiacus and Psoas Major
Sartorius
Longest muscle in the body. Aids in flexion of the hip and knee (sitting) and abducts and laterally rotates the thigh (sitting cross legged)
Adductor Muscles
Rotate and draw the thigh toward the body.
The group consists of:
Adductor Magnus
Adductor Brevis
Adductor Longus
Gracilis
Quadriceps Femoris
Most powerful muscle in the body, prime mover for knee extension. The 4 muscles are:
Vastus intermedius
Rectus Femoris
Vastus lateralis
Vastus medialis
Gluteus Medius
Abducts and rotates the thigh outward
Gluteus Maximus
The bulkiest muscle in the body, produces backswing of the leg when walking and power to climb stairs
Gluteus Minimus
This muscle lies beneath the other two gluteal muscles, assists medius in abducting the thigh when extended, aids both internally and externally rotating the thigh.
Hamstrings
Group of muscles consisting of three muscles which work to extend the thigh at the hip, flex the knee and rotate the leg.
Biceps Femoris
Semitendionsus
Semimembranosus
Calf Muscle
Made up of two muscles:
Gastrocnemius and Soleus
Contraction of these muscles causes plantar flexion of the foot
Calcaneal Tendon
Achilles Tendon
The common tendon of the gastrocnemius and soleus. It inserts on the calcaneus (heel bone)
largest tendon
Synergists
Help with movement of a bone
Antagonists
Work against movement/each other
Prime Mover
The main muscle triggering a movement
Fusiform
What is the longest muscle in the body?
Sartorius Muscle
What is the most powerful muscle in the body?
The quadriceps femoris
