channel proteins tails peripheral cell surface hydrophobic bilayer membrane heads proteins leaves acid phospholipid head fatty glycolipids fluidity carbohydrates attract cell integrals Cholesterol structure glycoproteins phosphate
The
is
a
fundamental
cell
,
regulating
what
enters
and
the
.
It
is
composed
of
a
phospholipid
.
Each
is
made
up
of
a
and
two
tails
.
The
are
hydrophilic
(
they
water
)
and
the
are
(
they
repel
it
)
.
It
also
has
.
If
the
proteins
partially
or
totally
cross
the
membrane
they
are
called
,
which
in
turn
can
be
or
transport
.
Those
that
are
at
the
are
called
.
is
another
component
of
a
fatty
nature
that
is
responsible
for
giving
to
the
membrane
.
Additionally
,
the
cell
membrane
presents
that
can
be
bound
to
or
lipids
.
The
former
are
known
as
and
the
latter
as
.