exam 2- muscle physiology, endocrine, reproductive Flashcards
what are the three types of muscle?
cardiac, skeletal, smooth
characteristics of cardiac muscle
striated (sarcoma), involuntary
characteristics of skeletal muscle
striated (sarcoma), voluntary
characteristics of smooth muscle
involuntary (no sarcoma)
the 4 properties of muscle are:
contractatility, excitability, extensibility, elasticity
contractility
the ability to generate force by contracting
excitability
the ability to respond to a stimulus (this is often from a motor neuron)
extensibility
stretch beyond resting length without being damaged
elasticity
ability to return to resting length after being stretched
what is the primary function of all muscle?
to generate force
what is the secondary function of skeletal muscle?
to maintain posture, stabilize joints, generate heat (shivering)
how are skeletal muscles attached to bones?
via tendons
what causes joint movement?
muscle tension on the tendon
origin of the muscle
the part of the muscle that is closer to the body. this part remains immobile during the action
insertion of the muscle
the part of the muscle that is farther from the body. this part moves during the action
what is the tendon connected to?
the bone on one end, and epimysium on other end
structure of the muscle, from smallest part to biggest:
muscle cell (fiber), endomysium (between the cell fibers), fasicle (wraps a group of fibers), perimysium (wraps the fasicles in groups), epimysium (wraps around the perimysium) and is attached to tendon, which is attached to bone
what does a parallel arrangement of fascicles tell you?
works for range of motion
what does a pennate arrangement of fascicles tell you?
works for power. you can fit more muscle cells into a space that is pennate vs parallel. more muscle cells = more force = power
where is calcium stored in the myofiber?
sarcoplasmic reticulum
what is the importance of the t-tubule in the myofiber?
propogates action potentials into the interior of the cell
what is the sarcomere?
it is the functional unit of muscle contraction. it gives rise to the striated appearance of cardiac and skeletal muscles
z-disk
protein structure that serves as a point of attachment for the thin myofilament. from one z-disk to another = one sarcomere
m-line
in the middle. a protein structure that acts as a place of attachment for the thick myofilaments