muscles Flashcards
where are muscles not located?
in porifera
where were muscles first found?
in annelids
what makes muscles work?
contracting and relaxing
what shape are cells in muscles?
cylindrical
what are the basic animal tissues?
smooth muscle cardiac, striated
what are characteristics of smooth muscles?
no striations one cell with one nucleus
what does visceral mean ?
guts
are muscle fibers tightly packed ?
yes
what are characteristics of the heart muscle?
involuntary, small short fibers, striation and uninucleate, intercalated disks
what is the most common type of muscle?
striated
what are muscles made of ?
bundles of muscle fibers
what are your muscle cells made of ?
myofibrils
what two proteins make up myofibril?
actin and myosin
what are actin and myosin?
proteins that make up myofibrils actin is a thin filliment and myosin is a thick filiment
what is a z line?
a vertical line that holds the actin filaments
what makes thin filaments
two strands of actin and other protein
what makes thick filaments?
myosin
what is the sliding filament theory of muscle contraction?
when contraction occurs the z lines move to the center of the srcomere which leads to much more overlap and the light areas will be much smaller.
what is the sliding filament theory of muscle contraction with thick filaments (myosin)
composed of 200 myosin molecules that have tails and heads. the heads have atp,.
what is the sliding filament theory of muscle contraction with thin filaments (actin)
mostly composed of actin, the troponin and tropomyosin are going to cover up the spots where the myosin heads would bind
what is the arrangement of sarcoplasmic reticulum?
each myofibril has a sarcoplasmic reticulum there has to be an axon that sends a signal to allow the myofibrils to be able to contract
