AKA striated Voluntary Muscle (nervous system provides voluntary control)
Has SOME ability to repair itself
T/F Muscle Cell = Muscle Fiber
True
Which muscle type is multinucleated?
Skeletal Muscle
What provides voluntary control of the Skeletal Muscle?
The nervous system
Skeletal Muscle Drugs target what receptor?
Nicotinic ACh receptor
______________ binding to its receptors stimulate skeletal muscles to contract
Acetylcholine
Skeletal Muscle Drugs target the Nicotinic ACh receptor
They are Cholinesterase inhibitors that decrease breakdown of ACh
Used as treatment for Myasthenia gravis
Name the 3 Beta Blocker, Cardiac Muscle Drugs (they block the affect of sympathetic nervous system stimulation.)
Metroprolol, Carvedilol, & Atenolol
Smooth Muscle Tissue:
Located in walls of blood vessles, around hollow organs (urinary bladder) & in layers around the respiratory, circulatory, digestive and reproductive tracts
Small, Spindle-Shaped cells, Single Nucleus
Have ability to divide, repair after injury, no striations
Referred to as NONSTRIATED INVOLUNTARY MUSCLE (nervous system, hormones can affect smooth muscle)
Which of the three muscle types is the only one that CANNOT repair itself?
Cardiac Muscle
Nonstriated Involuntary Muscle
Smooth Muscle Tissue
Smooth Muscle
Thick & Thin filaments are not organized
Thick filaments scattered throughout the sarcoplasm
Thin filaments are attached to dense bodies
Smooth Muscle
Dense Bodies
Composed of desmin
Not arranged in straight line, so contractions cause cell to twist (corkscrew)
Bind together adjacent smooth muscle cells
T/F: Dense bodies are arranged in a straight line.
FALSE. Not arranged in straight line, so contractions cause cell to twist
What are dense bodies composed of?
Desmin
Where are thin filaments found?
Thin filaments are attached to dense bodies
Where are thick filaments found?
Thick filaments are scattered throughout the sarcoplasm
Unipennate: Muscle fiber on one side of tendon (ex. extensor digitorum muscle)
Bipennate: Muscle fibers on both sides of tendon (ex. rectus femoris)
Multipennate: When tendon branches within a pennate muscle (ex. deltoid muscle)
* b/c muscle fibers pull at an angle, not as much movement is produced as parallel muscles*
Levers (how muscle moves in relationship to bone and joint)
First-Class Lever
Seesaw: fulcrum is between applied force & load (lifting head)
Levers (how muscle moves in relationship to bone and joint)
Second-Class Lever
Wheelbarrow: Fulcrum on end, load in middle (ex. raising up on toes)
Levers (how muscle moves in relationship to bone and joint)
Third-Class Lever
Most common in body, applied force is between load and fulcrum (ex. contracting bicep muscle to lift arms)
Of the three lever systems which is the most common in our body?
Third-Class Lever
Lifting head up is an example of which of the following?
C. First-Class Lever
The wheelbarrow scenario is an example of which of the following?
A. Second-Class Lever
Muscle Terminology ORIGIN: Fixed end INSERTION: Free (movable) end
Action: Movement AGONIST: main muscle repsonsible for movement ANTAGONIST: muscle who's action opposes a particular agonist
Muscle Terminology:
Fixed end
Origin
Muscle Terminology:
Free (moveable) end
Insertion
Muscle Terminology:
Main Muscle responsible for movement
Agonist
Muscle Terminology:
Muscle who's action opposes a particular agonist
Antagonist
Muscles of Mastication (aka chewing) Buccinator-Moves food around in mouth Masseter-Elevates mandible, closes jaw Temporalis- elevates mandible
Pterygoids (medial & lateral) Medial- closes jaw Lateral- opens jaw
Muscles of Mastication
Moves food around in mouth
Buccinator
Muscles of Mastication
Elevates mandible, closes jaw
Masseter
Muscles of Mastication
Elevates Mandible
Temporalis
Muscles of Mastication
Pterygoids: CLOSES jaws
Medial
Muscles of Mastication
Pterygoids: Opens jaws
Lateral
Extrinsic Eye Muscles:
Inferior Rectus:Eyes look down
Medial Rectus: Eyes look medially
Lateral Rectus: Eye looks laterally
Superior Rectus: Eye looks up
Inferior Oblique: Eye rolls, looks up & laterally
Superior Oblique: Eye rolls, looks down & laterally
If superior rectus is contracting the eye will look _______
up
If inferior rectus is contracting the eye will look _______
down
If superior oblique is contracting the eye will _______
Compresses abdomen, depresses ribs, flexes or bends spine
Which of the following flexes the vertebral column?
B. Rectus Abdominus
Which of the following (more than one) compresses abdomen, depresses ribs, flexes or bends spine?
1. Rectus abdominus
2. Internal Oblique
3. External Oblique
4. Superior Oblique
5. Inferior Oblique
2. Internal Oblique
3. External Oblique
Muscles in the upper body:
The muscle forming the rounded contour of the shoulder
Large superficial muscle that extends longitudinally from the occipital bone to the lower thoracic vertebrae and laterally to the spine of the scapula (shoulder blade). Its functions are to move the scapulae and support the arm.
Trapezius
Muscles in the Upper Body:
Important for breathing because it elevates and depresses ribs
