There
are
more
than
600
muscles
in
the
human
body
.
Muscles
have
a
variety
of
functions
,
such
as
pumping
blood
,
supporting
movement
or
____________________
birth
.
Muscles
work
by
either
contracting
or
____________________
to
cause
movement
.
This
movement
may
be
voluntary
(
meaning
the
movement
is
made
____________________
)
or
____________________
(
i
.
e
.
done
without
our
conscious
awareness
)
.
The
three
main
types
of
muscle
tissue
include
:
?
Skeletal
muscle
is
____________________
to
bones
and
allows
movement
.
Together
,
skeletal
muscles
and
bones
are
called
the
musculoskeletal
system
(
also
known
as
the
locomotor
____________________
)
.
Skeletal
muscles
are
grouped
into
opposing
pairs
such
as
the
biceps
and
____________________
on
the
____________________
and
back
of
the
upper
arm
.
Skeletal
muscles
are
under
our
____________________
control
,
which
is
why
they
are
called
voluntary
muscles
.
Another
term
is
____________________
muscles
,
since
the
tissue
looks
striped
when
viewed
under
a
microscope
.
?
Cardiac
muscles
are
located
in
your
heart
only
.
They
help
your
heart
____________________
blood
throughout
your
body
.
They
are
involuntary
muscles
that
your
____________________
nervous
system
controls
.
That
means
they
work
without
you
having
to
____________________
about
it
.
?
Smooth
muscle
____________________
up
your
organs
,
blood
____________________
,
____________________
tract
,
skin
and
other
areas
.
Smooth
muscles
are
involuntary
.
That
means
that
your
autonomic
nervous
system
controls
them
or
,
in
other
words
,
the
motion
of
smooth
muscle
happens
without
our
conscious
____________________
.
The
____________________
of
the
muscles
in
your
body
are
skeletal
muscles
.
They
are
the
muscles
that
allow
you
to
____________________
a
wide
range
of
movements
and
functions
.
____________________
(
tough
bands
of
connective
tissue
)
attach
skeletal
muscle
tissue
to
____________________
throughout
your
body
.
Your
shoulder
muscles
,
____________________
muscles
and
abdominal
muscles
are
all
examples
of
skeletal
muscles
.