Unit 4: Ch 10 (Muscular System) Flashcards
Action
- Effect produced by a muscle, either to produce a movement or prevent it
Three muscle tissues
- Cardiac muscle
- Skeletal muscle
- Smooth muscle
Function, Location of:
Synergist
- Helper muscle to the prime mover
- On the same side of bone as the prime mover
Endomysium
sleeve surrounding the muscle fibers
- contains blood capillaries and nerve fibers
- also provides chemical environment for exchange of ions
- areolar connective tissue
Functions of Muscles
- Glycemic control: regulates blood glucose levels
- Heat production (thermogenesis): heat generation & regulation of body temperature
- Movement: gross movement (ie joints)
- Control of orifices
- Peristalsis: smooth muscle that moves food through the GI system
- Stability: posture
Nomenclature: Attachment site
- Name of a bone in its name
- Example: femorous
Innervation
Nerve fibers entering muscles
- these are the nerves that tell the muscle to contract
- 2 groups
- Spinal nerves
- Cranial nerves
Structure, Location, Striations, Control:
Cardiac muscle
- pumps blood;
-
Intercalated discs that operate as gap junctions
- Zigzag appearance
- Striated
- Involuntary contraction
- Found in the heart
Card A
Function, Location:
Antagonist
- Relaxes and extends as the prime mover contracts
- On the opposite side of the prime mover
Form, Function of:
Fascicles
- A bundle of skeletal muscle fibers
- a “compartment of” bundled muscle fibers within a epimysium, also contains nerves and blood vessels
- Determines the strength of a muscle and the direction in which it pulls
aponeurosis
broad sheet-like tendon
tendon
bridges the gap between muscle and bone
Nomenclature: Fiber direction
- Refers to a plane in its name
- Example: Internal abdominal oblique
Belly (body)
- Largest portion of muscle capable of contraction
Nomenclature: Size
- “Major, magnus, minor”
- Example: Pectoralis minor
sarcomeres
segment of myofibril that shortens to contract the muscle
from one Z disc to the next
Fascia
Protective sheath forming compartments around neighboring muscles and other tissues
Epimysium
fibrous sheath around the muscle, grades into the fascia
- surrounds the entire muscle/organ
- provides strength in all 3 planes
- dense irreg connective tissue
Structure, Location, Function, Control:
Skeletal muscle
- Voluntary contraction
- Striated muscle
- Attached to the bones
- Multi nuclei on the periphery of the cell
- Uses skeleton as an anchor for action
Nomenclature: Number of origins
- # of locations where muscle orginates from bone
- Example: biceps brachii
myofibrils
long protein cords within a muscle fiber
tendon sheath
a type of bursae that form tunnels for tendons to slide through
Nomenclature: Shape
- Partially identified by the shape
- Example: Trapezius
Muscle germ layer
- Mesoderm
Muscle fiber
a single skeletal muscle cell;
- long;
- contains myofibrils
- wrapped in endomysium
Origin
- attachment at the “fixed end”
- Immobile portion acting as an anchor
Prime mover (agonist)
- The primary muscle doing the contracting
- Typically generates the most force
Perimysium
- thick sheath that bundles fascicles together
- carries larger blood vessels, nerves, and stretch receptors
- dense irreg connective tissue
Structure, Location, Function, Control:
Smooth muscle
- typically Involuntary,
- responds to a variety of stimuli
- Nonstriated muscle (its reason for its name)
- Most organs & digestive system
- example:esophogus
thin filament
and
thick filament
a protein strands that carries out contraction;
- thin filaments are composed of actin
- thick filaments are composed of myosin
Insertion
- attachment at the “moving end”
- the distal, freely moving bone of its joint
Muscle nomenclature
- Naming muscles
- Fiber direction (ie transverse, oblique)
- Attachment site (ie name of bone)
- Size (ie major, minor, magnus)
- Shape (ie trapezius, orbicularis)
- Function (ie adductor, abductor, flexor)
- Number of origins (ie biceps, quadriceps, triceps)
Nomenclature: Function
- What results after a muscular contraction
- Example: Adductor longus
