A&P Test 3 Flashcards
what percent of body mass is contributed to skeletal muscle mass?
40%
What is skeletal muscle important for?
defend itself
provide for itself
communication
what does the skeletal muscle store to use as energy?
glycogen
what is stored in the muscle?
ions
glycogen
fluids
proteins
what are effectors?
something that receives instructions from the CNS
what is a glycogen?
a bunch of glucose molecules stuck together. a large starch compound.
Where is glycogen stored besides the muscles?
Liver
glycogen is broken down into
glucose
what does a ligament connect?
bone to bone
what does a tendon connect?
usually muscle to bone
however
sometimes it is muscle to muscle via an intermediary tendon (tendon bridge)
individual muscle cells are called
muscle fibers
more than one group of muscle cells are called a
fasciculous. These function as a unit
many fasciculous together are called
muscle
what are the internal cylinders called that are in a muscle fiber?
myofibril
what do myofibrils contain?
actin and myosin
how many myofibrils are in a muscle per skeletal muscle cell?
> 200 in smaller muscles
thousands in a larger cell in a larger muscle
what are skeletal muscle cells with little moyfibrils good for?
fine motor control
(don’t want to squeeze a glass with a ton of strength because it will crush it)
what is the basic contractile unit of a myofibril?
a sarcomere
what are the thick contractile units of a sarcomere called?
Myosin filament
what are the thinner contractile units of a sarcomere called?
actin filament
what is the area of overlap between a myosin and actin called?
A band
what does the overlap of actin and myosin allow for?
force
what is a motor unit?
one or more skeletal muscle fibers that are controlled by a single motor neuron
how many skeletal muscles cells can a motor neuron control?
one or many