Muscles and Muscle Tissue
name the three types of muscles
smooth, cardiac, skeleton
location of smooth muscle
skin, walls of hallow organs
control of smooth muscle
involuntary
branching of smooth muscle
no
striations of smooth muscles
no
intercalated discs in smooth nucleus
no
nucleus location in smooth muscle
single and central
cell shape in smooth muscle
spindle
location of cardiac muscle
heart
control of cardiac muscle
involuntary
branching of cardiac muscle
yes
striations in cardiac muscle
yes
intercalated discs in cardiac muscle
yes
nucleus location in cardiac muscle
single and usually central
cell shape of cardiac muscle
branched cylinder
location of skeleton muscle
attached to bones
control of skeleton muscle
voluntary
branching in skeleton muscle
no
striations in skeleton muscle
yes
intercalated disc in skeleton muscle
no
nucleus location in skeleton muscle
multiple and peripheral
shape of skeleton muscle
cylinder
what does myo or sacro mean
muscles
what are the special characteristics of muscles
excitability, contractibility, extensibility, elasticity
what is excitability in a muscle
responsiveness to stimuli
what is contractibility
able to shorten after stimuli
what is extensibility
ability to extend or stretch
what is elasticity
ability to recoil back in length after being stretched
what is the function of muscles
produce movement, maintain posture and body position, stabilize joints, generate heat, protects the internal organs
muscular tissue consists of
nerves, blood vessels, connect tissue sheath, muscles
what connective tissue sheaths are in muscular tissues
epimysium, perimysium, endomysium
what is epimysium
dense irregular connective tissue that surround the whole muscle
what is perimysium
connective tissue that surround the muscle fascicle or muscle bundles
what is endomysium
connective tissue that surrounds each individual muscle fiber
the attachment of origin and insertion of muscle can be __________ or ____________.
direct or indirect
what happens in direct attachment
the epimysium is fused direction to the periosteum or perichondrium
what happens in indirect attachment
epimysium extends beyond the muscle either as a rope like tendon or sheet like aponeurosis, which is attached to the bone or surround muscle
what is the cell membrane of the muscle cell called
sarcolemma
what is the cytoplasma of the muscle cell called
sarcoplasm
what is the diameter of a muscle cell
10-100 micrometer
what is the length of a muscle cell
up to 30cm
what does the sarcoplasma contain
glycosomes and myoglobin
what are glycosomes
granules of stored glycogen that provide glucose during muscle cell activity
what are myoglobin
red pigment that store oxygen
each muscle cell contains thousands of rod like ________________ that run ___________
myofibril, parallel to each other
how much of the muscle fiber is myofibrils
80%
what is the contractile unit of the muscle
sarcomere
each sarcomere consists of
contractile protein
a contractile protein consists of
myosin, actin, regulatory, a band, h zone, m line, I band, z line
what is myosin
thick myofilament, has a tail and head
what does the head of a myosin have
an ATP binding site and an actin binding site
what is actin
thin myofilament, two actin protein strands twisted over each other
what does the actin have
a myosin binding site
what is tropomyosin
regulatory protein, when muscle is relaxed it does not allow the two binding sites to meet
what is troponin
keep the tropmyosin in place when the muscle is relaxed
location of a band
extends from one end of myosin to the other end of myosin
location of h zone
part of sarcomere within the a band where there is only myosin
location of m line
part of sarcomere within the a band in the center of the h zone which consists of the myosin myofilaments to each other
location of I band
part of sarcomere where we see only actin myofilaments
location of z line
part of sarcomere within the I band where adjacent actin myofilimanet are connected together
where does a sarcomere extend to
from one z line to the other z line
which lines do not change size
m, z, a
sliding filament theory of muscle contraction
calcium comes into muscle cell. reposition of regulatory protein. actin binding sites of myosin bind to the myosin binding site of actin. uses energy from ATP and creates a rowing action preformed by myosin.
the rowing action of myosin results in
h zone decrease. shortening of I bond, shortening of sarcomere, shortening of myofilament, shortening of muscle fiber, shortening of muscle bundle, shortening of muscle.