(^1) NERVE CELLS
Found in the brain, spinal cord, and
nerves, nerve cells, or neurons, carry
and process high-speed electrical
signals, called nerve impulses. These
impulses coordinate body processes
and enable us to feel, think, and move.
(^2) WHITE BLOOD CELLS
Circulating in blood, and in a clear fluid
known as lymph, white blood cells help
defend the body against disease. The
cells include macrophages and neutrophils,
which eat bacteria and other germs, and
also lymphocytes, which release germ-
disabling antibodies.
(^3) EPITHELIAL CELLS
Tightly packed together, these cells provide
a barrier to stop harmful chemicals and
germs reaching body tissues. They cover
the body, forming the outer layer of skin,
and line hollow organs such as the
stomach, lungs, and bladder.
(^4) BONE CELLS
Osteocytes are bone cells that help
to keep the bone in good condition.
At first, they lay down bone, but
later become stranded within a bony
space. They keep in touch through
tiny threads and pick up supplies
from nearby blood vessels.
(^5) LIVER CELLS
Also known as hepatocytes, liver
cells enable the liver to perform many
hundreds of roles to control blood
composition and keep the body stable.
These include processing and storing
nutrients (foods), and removing poisons.
(^6) FAT CELLS
As their name suggests, fat cells
specialize in storing fat. They group
together to form adipose tissue, which
serves as an energy store, cushions
organs such as the kidneys, and
insulates the body under the skin.
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A spherical fat
cell is filled
mostly with
a droplet of
energy-rich fat
Spiky osteocyte lives
in a lacuna, or space,
in the bone matrix
Bone matrix is made
of hard calcium salts
and more flexible
collagen fibres
Epithelial cells lock
together to form
the protective, pitted
lining of the stomach
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062_063_Cells.indd 63 03/01/19 12:09 PM
elle
(Elle)
#1