MUSCLES Flashcards
3 types of muscle
skeletal ( produce joint movement/ support) , smooth (organs and blood vessels) cardiac (heart muscles)
What is fascia
connective tissue that surrounds organs, muscles, bones, vessels, nerves within the body
How does fascia change at it gets deeper?
loose connective tissue superficially and transitions to dense connective tissue.
what is fascia’s role
to support, separate, reduce friction, and interconnect structures in body
What does fascia form and what do they do
forms muscle seperators that compartmelize muscles and support nerves and vessels in the area
Does fascia have nerves and blood vessels?
yes- they respond to stress like any other tissue
define tendons
connection between muscles and bones. Muscles have tendon at each end
define ligaments
connection between bones
what are tendons and an example
fascia that surrounds the muscles blend into tendon structure. The tissue of tendons interweave with the fibers of the bone. Example is Achilles tendon
what are ligaments
ligament fibers interweave into bone fibres at either end.
what is a common ligament
ACL (anterior cruciate ligament)
define origin of muscle
where a muscle tendon joins a relitively stable skeleteal structure.
is the orgin of a muscle usually proximal or distal
proximal
define insertion
point where distal muscle tendon attatches to moving bone
is the insertion of a muscle proximal or distal
distal
define function
when the muscle moves its insertion toward its orgin
define concentric
muscle shortening causes joint movement
define essentric
muscle lengthens while developing tension (slowly lowering weight)
define isometric
muscle length does not change. attempts to shorten but cannot
define joint action
movement that occurs at joint itself
define muscle action
muscle contraction is occuring
define agonist muscle
muscle in the process of contracting. can be essentric, conncentric, or isometric
define antagonist muscle
muscle that opposes the agonist and relaxes when agonist contracts
define fasicles
bundle of muscle fibers
4 skeletal muscle shapes
parallel (fusiform vs non fusiform)
pennate (unipennate, bipennate, multipennate
convergent
circular
describe parallel non fusiform and example
muscle has consistent diamter, sartorius
describe parallel fusiform and example
the muscles mid belly has largest diamter and then taper at each end. Biceps brachii
parallel muscle definition:
characterized by fasicles running parallel to one another. Most abundant muscle type
pennate muscle definition:
tendon runs the length of muscle and fasicles pull on tendon at varying angles
what is unipennate muscle and example
all fasicles on same side of tendon extensor digitorium of hand
what is bipennate and example
fasicles lie on either sides of tendon rectus femoris
what is multipennate and example
if central tendon splits/ more than one central tendon with pennation. deltoid
what muscle can undergo quicker muscle contractions
parallel
which muscle can generate greater force. pennate or parallel
pennate
what shape are convergent muscles
triangular shape
in convergent, do all muscles run parallel
no they do not
in circular muscles does muscle contractions shrink or widen the opening
muscle contractions shrink the opening while relaxation widens it
example of convergent muscle
pectoralis major
example of circular muscle
orbicularis oris (kissing muscle)
why can parallel muscles undergo quicker muscle contractions
because parallel pull along axis whereas pennate pull at an angle
why can pennate muscles generate a greater force than paralell
because there are more fasicles per unit area.
