FINAL 02 - Muscular System Flashcards
Are responsible for all types of body movement
Muscles
2 prefixes that refer to “muscle”
myo-, mys-
Prefix that refers to “flesh”
Sarco-
Individual muscle cells that make up the skeletal muscles
Muscle fiber
Specialized plasma membrane
Sarcolemma
Long organelles inside muscle cell
Myofibrils
Light band; contains only thin filaments
I band
Dark band; contains the entire length of the thick filaments
A band
Center of each sarcomere which consists only of myosin myofilaments
H zone
The myosin myofilaments are anchored in the center of the sarcomere
M line
Contractile unit of a muscle fiber
Sarcomere
Specialized smooth endoplasmic reticulum
Sarcoplasmic reticulum
7 ways to name muscles
Location, Size, Shape, Orientation, Origin and insertion, Number of heads, Function
Attachment to an immovable bone
Origin
Attachment to a movable bone
Insertion
2 types of body movements
Flexion, Extension
Decreases the angle of the joint
Flexion
Increases angle between two bones
Extension
Extension between 180°
Hyperextension
Movement of a bone around its longitudinal axis
Rotation
Movement of a limb away from the midline
Abduction
Movement of a limb toward the midline
Adduction
Combination of flexion, extension, abduction, and adduction
Circumduction
Lifting the foot so that the superior surface approaches the shin
Dorsiflexion
Depressing the foot/pointing the toes
Plantar flexion
Turn sole of foot medially
Inversion
Turn sole of foot laterally
Eversion
Forearm rotates laterally so palm faces anteriorly
Supination
Forearm rotates medially so palm faces posteriorly
Pronation
Move thumb to touch the tips of other fingers on the same hand
Opposition
Adducts and flexes the humerus
Pectoralis major
Raise rib cage during inhalation
External intercostals
Depress the rib cage to move air out of the lungs when you exhale forcibly
Internal intercostals
Inspiration; elevates the ribs
Scalene
Flexes vertebral column and compresses abdominal contents
Rectus abdominis
Compresses abdominal contents
Transversus abdominis
Flexes vertebral column; rotates trunk and bends it laterally
External and internal oblique
Elevates, depresses, adducts, and stabilizes the scapula
Trapezius
Extends and adducts the humerus
Latissimus dorsi
Flexes the spine laterally
Quadratus lumborum
Arm abduction
Deltoid
Back extension
Erector spinae
Supinates forearm, flexes elbow
Biceps brachii
Elbow flexion
Brachialis
Weak muscle; elbow flexion
Brachioradialis
Elbow extension (antagonist to biceps brachii)
Triceps brachii
Wrist flexion
Flexor carpi
Finger flexion
Flexor digitorum
Wrist extension
Extensor carpi
Finger extension
Extensor digitorum
Hip extension
Gluteus maximus
Hip abduction; steadies pelvis when walking
Gluteus medius
Hip flexion; keeps the upper body from falling backward when standing erect
Iliopsoas
Adduct the thighs
Adductor muscles
Thigh extension and knee flexion
Hamstring group
Flexes the thigh
Sartorius
Extends the knee
Quadriceps group
Dorsiflexion; foot inversion
Tibialis anterior
Toe extension and dorsiflexion of the foot
Extensor digitorum longus
Planter flexion; foot eversion
Fibularis muscles
Plantar flexion
Soleus
Compresses the cheeks and lips against teeth
Buccinator
Depresses the angle of the mouth
Depressor anguli oris
Raises the upper lip
Levator labii superioris
Raises the eyebrows
Occipitofrontalis
Closes the eyelids
Orbicularis oculi
Draws out the angle of the mouth
Risorius
Elevates and abducts the upper lip
Zygomaticus major/minor
Elevates and retracts the mandible
Temporalis
Elevates and protracts mandible
Masseter
Retracts and depresses mandible
Lateral pterygoid
Protracts and elevates mandible
Medial pterygoid
Flexors and extensors of the neck
Neck flexor and extensor
Individually rotates the head
Sternocleidomastoid
Extends the head and neck
Trapezius
Depresses the mandible
Platysma