Chapter 1: Structure and Function of the Muscular, Nervous, and Skeletal Systems Flashcards
Each skeletal muscle is surrounded by a later of connective tissue called
epimysium
bundles of muscle fibers
fascicles
connective tissue forming fascicles
perimysium
connective tissue surrounding individual muscle fibers
endomysium
These help transmit the force of muscle action to the bone
connective tissue (epi, peri, endo-mysium)
plasma membrane of a muscle cell
sacrolemma
electrical impulses to the MF
action potentials
cytoplasm of the MF
sacroplasm
organelle that stores aclcium and regulates the muscle action process by altering the inracellular calcium concentration
sarcoplasmic reticulum
channels that form openings in the sacrolemma, and conduct AP
transverse tubules
column of protein structures that run parallel to the length of the muscle fiber
myofibrils
each myofibril is a budle of these
myofilaments
two primary myofilaments
myosin (thick)
actin (thin)
this protein acts to maintain the position of the myosin filament relative to actin
titan
two regulatory proteins associated with actin
tropomyosin
troponin
spans the length of 7 G-actin proteins along the length of the actin filament
tropomyosin
each end of the tropomyosin filament is attached to this
troponin
this protein acts to ensure the correct length of the actin filaments
nebulin
basic contractile unit of the muscle
sacromere
The sarcomere extends from here to here
z-line to z-line
This is determined by the width of the myosin filament
A-band (dark band)
Actin filaments are anchored here
z-line
the area of the a band that contains myosin by not actin
H-zone
this middle of the H-zone is a dark line called the
M-line
this helps align adjacent myosin filaments
M-line
this section is composed of only actin, and crosses two sarcomeres
I-band (light band)
communication between the nervous and muscle systems occurs here
neuromuscular junction
the specialized region on the muscle cell membrane at the NMJ
motor endplate
enzyme responsible for spliting the fresh ATP and re-energizing the myosin head during the sliding filament theory
adenosine triphosphatase
according to this theory, a muscle shortens or lengthens because the actin and myosin filaments slide past eachother without the filaments themselves changing length
sliding filament theory