Chapter 11 - Muscular System pt 2 Flashcards
Anatomical position is also known as ____?
Zero position
What type of movement decreases joint angle?
Flexion
What type of movement straightens joint angle?
Extension
What type of movement straightens joint angle beyond zero position?
Hyperextension
Flexion and extension usually occur in which plane?
Sagittal
What type of movement moves away from midline?
Abduction
What type of movement moves toward the midline?
Adduction
Abduction and Adduction usually occur in which plane?
Frontal
What type of movement raises a body part?
Elevation
What type of movement lowers a body part?
Depression
Elevation and depression usually occur in which plane?
Frontal
What type of movement creates an anterior movement? (ex: shoulders moving forward)
Protraction
What type of movement creates a posterior movement? (ex: shoulders moving backward and pushing chest out)
Retraction
Protraction and retraction usually occur in which plane?
Transverse
What type of movement occurs when the distal end of a limb makes a circle while the proximal end is stationary?
Circumduction
What type of movement happens when a bone spins on its long (lateral) axis?
Rotation
What is the difference in external and medial rotation?
External rotation the anterior surface spins away from the midline, in medial rotation the anterior surface spins towards the midline
What type of movement moves the palm to face anteriorly?
Supination (radius and ulna become parallel)
What type of movement moves the palm to face posteriorly?
Pronation (radius crosses ulna)
What are the four special movements of the mandible?
- Protraction (moving jaw forward)
- Retraction (moving jaw backward)
- Lateral excursion (moving jaw to side while chewing)
- Medial excursion (moving jaw back towards center)
Give examples of how muscles are named by size
Maximum Medius Minimus Longus Brevis Vastus
Give examples of how muscles are named by shape
Deltoid (delta/triangle)
Trapezius
Latissimus (wide)
Teres (round)
Give examples of how muscles are named by orientation of fibers
Rectus
Orbicularis
Transverse
Oblique
Give examples of how muscles are named by location (specific body regions)
Frontalis
Femoris
Brachii
Give examples of how muscles are named by attachment
Attachment sites on bones
Formerly referred to as origin and insertion
Give examples of how muscles are named by number of attachments
Biceps
Triceps
Quadriceps
Give examples of how muscles are named by action
Flexor
Extensor
Adductor
Levator
What is action in terms of muscles?
Movement produced by a muscle
What are the 4 actions of muscle groups?
- Prime Mover (agonist)
- Synergist
- Antagonist
- Fixator
What does the Prime Mover (agonist) do? Example?
Produces most of the force
Ex: brachialis when flexing the elbow
What does the Synergist do? Example?
Muscle that aids the prime mover
May stabilize joint and restrict unwanted movement
Ex: Biceps brachii working with the brachialis when flexing elbow
What does the Antagonist do? Example?
Muscle that opposes the prime mover
Exerts braking action and makes action smoother
Ex: Triceps brachii antagonistic to brachialis
What does the Fixator do? Example?
Muscle that restricts bone from moving
Allows another muscle attached to pull on something else
Muscle fibers are organized into _____
Fascicles
What are the four patterns of fascicle arrangements?
- Circular
- Parallel
- Convergent
- Pennate
Describe circular fascicles
- Concentrically arranged around an opening
- Acts as a sphincter to close a passageway or opening (ex: orbits, mouth, anus)
Describe parallel fascicles
- Parallel to the long axis of the muscle
- Body of muscle increases in diameter with contraction
- Not very strong, lots of endurance
Describe convergent fascicles
- Triangular muscle with common attachment site
- Direction of pull of muscle can be changed
- Does not pull as hard as equal-sized parallel muscle
Describe pennate fascicles and their 3 subtypes
- Fascicles arranged obliquely to one or more tendons
- Pulls harder than a parallel muscle of equal size
- Unipennate: muscle fibers on one side of tendon
- Bipennate: muscle fibers on both sides of tendon
- Multipennate: tendon branches within muscle
What are the two (typically) strongest types of muscle fascicles?
Bipennate and Multipennate
What are intrinsic muscles?
Both attachments (origin and insertion) contained within a particular region
What are extrinsic muscles?
Acts upon a designated region but has its origin elsewhere
