Muscles and Tissues

Single layer of flattened cells
with disc-shaped central nuclei and sparse
cytoplasm; the simplest of the epithelia

Allows materials to pass by
diffusion and filtration in sites where protection
is not important; secretes lubricating
suostances in serosae

Kidney glomeruli; air sacs of lungs;
lining of heart, blood vessels, and lymphatic
vessels; lining of ventral body cavity (serosae)

Single layer of cubelike cells
with large, spherical central nuclei

Secretion and absorption

Kidney tubules; ducts and secretory
portions of small glands; ovary surface

Single layer of tall cells with
round to oval nuclei; some cells bear cilia;
layer may contain mucus-secreting
unicellular glands (goblet cells)

Absorption: secretion of mucus.
enzymes, and other substances; ciliated type
propels mucus (or reproductive cells) by
Ciliary action

Nonciliated type lines most of
the digestive tract (stomach to rectum),
gallbladder, and excretory ducts of some
glands; ciliated variety lines small bronchi,
uterine tubes, and some regions of the uterus

Single layer of cells of differing
heights, some not reaching the free surface;
nuclei seen at different levels: mav contain
mucus-secreting goblet cells and bear cilia

Secretes substances, particularly
mucus; propulsion of mucus by ciliary action

Nonciliated type in male's
sperm-carrying ducts and ducts of large
glands; ciliated variety lines the trachea, most
of the upper respiratory tract

Thick membrane composed of
several cell layers; basal cells are cuboidal or
columnar and metabolically active; surface
cells are flattened (squamous); in the
keratinized type, the surface cells are full of
keratin and dead; basal cells are active in
mitosis and produce the cells of the more
superficial layers

Protects underlying tissues in
areas subjected to abrasion

Non-keratinized type forms the
moist linings of the esophagus, mouth, and
vagina; keratinized variety forms the
epidermis of the skin, a dry membrane

Generally two
layers of cubelike cells

Protection

Largest ducts of sweat glands,
mammary glands, and salivary glands

Several cell layers;
basal cells usually cuboidal;
superficial cells elongated
and columnar

Protection; secretion

Rare in the body; small
amounts in male urethra and in large ducts
of some glands

Resembles both stratified
squamous and stratified cuboidal: basal cells
cuboidal or columnar: surface cells dome
shaped or squamouslike, depending on
degree of organ stretch

Stretches readily and permits
distension of urinarv organ by contained urine

Lines the ureters, urinary bladder,
and part of the urethra

Long, cylindrical, multinucleate
cells: obvious striations

Voluntary movement; locomotion;
manipulation of the environment; facial
expression; voluntary control

In skeletal muscles attached to
bones or occasionally to skin

Branching, striated, generally
uninucleate cells that interdigitate at
specialized junctions called intercalated discs

As it contracts, cardiac muscle
propels blood into the circulation; involuntary
control

The walls of the heart

Spindle-shaped cells with
central nuclei; no striations; cells arranged
closely to form sheets

Propels substances (foodstuffs,
urine) or a baby along internal passageways;
involuntary control

Mostlv in the walls of hollow
organs (digestive and urinary tract organs, uterus, blood vessels)
Smooth Muscle