| Answer |
The body has more than how many muscles | 600 |
How much of our body weight is skeletal | 40% to 50% |
What determines purposeful body movement | The manner in which muscles are grouped, the relationship of muscles to joints, and how muscles attach to the skeleton |
Connective Tissue Components | 1)Endomysium
2) Perimysium
3)Epimysium |
Epimysium can | Fuse to become a tendon or aponeurosis |
The Endomysium | a delicate connective tissue membrane that covers skeletal muscle fibers
(individual muscle fibers) |
The Perimysium | a tough connective tissue binding fascicles
(envelopes bundles of muscle fiber) |
The epimysium | a coarse sheath covering the muscle as a whole |
Parallel muscle shapes | long with tendinous intersection/
Rectus abdominis, Sartorius (most typical shape) |
Convergent muscle shape | Pectoralis major (blades in a fan) |
Pennate muscle shape | Unipennate, Bipennate, Multipennate, Flexor pollicis longus, Rectus femoris and Deltoid (feather like) |
Fusiform muscle shape | Brachioradialis (parallel in the center or "belly" of the muscle but converge to a tendon at one end or both) |
Spiral muscle shape | Latissimus dorsi (twist between point of attachment) |
circular muscle shape | Orbicularis oris ( found around the mouth, eye and sphincters around the anus) |
What is the Origin | The point of attachment that does not move when the muscle contracts |
What is the Insertion | The point of attachment that moves when the muscle contracts |
The Origin bone is | The more stationary of the two bones at a joint when contractions occur |
Muscles have multiple | points of origins or insertions |
Origins and insertion | are points that may change under certain circumstances. |
Muscle contraction move bones which serve as | Levers, and by acting on joints, which serve as fulcrums for those levers |
What movements are produced by the coordinated action of several muscles | 1) Prime movers 2)Agonist 3)Antagonist
4)Synergists 5) Fixator muscle |
A prime mover is | A muscle that directly performs a specific movement |
A Agonists is | any mover muscles that directly perform a movement, including the prime mover |
Antagonists are | muscles that directly oppose prime movers when contracting; they relax while the prime mover is contracting to produce movement |
Antagonists also | provide precision and control durning contraction of prime movers |
Synergist are | muscles that contract at the same time as the PRIME MOVERS they facilitate prime mover actions to produce a efficient movement |
Fixator muscles are | joint stabilizers |
The Posterior portion of the deltoid muscle tenses to stabilize the shoulder joint, thus acting as a what | fixator muscles |
A Lever system is composed of four parts, what are they | 1) Ridget bar(bone) 2) Fulcrum (joint in which the rod moves)
3) Load ( moves) 4) Pull that produces movement /muscle contraction |
In the Human body | bones serve as levers, and joints serve as fulcrums |
The third class levers is | the most commonly used in the body |
Flexing the forearm at the elbow joint | is a commonly used example of a third-class lever |
Muscles are named according to one or more of the following | 1)Location, Function and type 2) Direction of fibers 3) Number of heads or divisions 4)Points of attachment/ Origin and insertion points 5) Relative size/ small medium or large |