ORGANIZATION OF THE BODY
TISSUES: EPITHELIUM
There are four basic tissues of the body: epithelial connective muscle and nervous.
Epithelial tissues (epithelium) form the body surface(skin), the surfaces of the body cavities and their contained
viscera, glands and all tubular organs, e.g., ducts and vessels.
Neuroepithelia convey sensations. Epithelia are arranged into single (simple) or several (stratified) layers. Their cells
are bound together by specialized fibers and substances (e.g., the basement membrane). Issues are generally
sensitive but avascular and receive the nutrition by diffusion.
Simple Epithelium:
Surface tissue functioning infiltration, diffusion, secretion, and absorption.
Squamous- Simple squamous it is a line the heart internal surfaces of all blood and lymph vessels and (endothelia),
the air cells of the lungs filtration capsules and theme tubules in the kidneys and the major body cavities
(mesothelia). Rapid diffusion of gases in solution or characteristic activities in these cells.
Cuboidal- simple cuboidal epithelium are generally secretory cells and makeup glands throughout the body, tubules
of the kidney, terminal bronchioles of lungs and ducts of the reproductive tracts.
Columnar- simple columnar epithelium lining the gastrointestinal tract and or concerns secretion and absorption.
There free (apical) surface may be covered with finger like projections of cell membrane called microvilli, increasing
the cell surface area for secretion/ absorption.
Pseudostratified columnar- this tissue consists of simple columnar cells together with irregularly placed nuclei giving
the appearance of multiple layers. However, each of the cells is attached to the basement membrane. This tissue
lines the of the reproductive tract and air conduction pathways of the respiratory tract. They often exhibit cilia on their
free surfaces at contain unicellular goblet shape secretory cells. The cilia collectively move surface material by virtue
of undulating power strokes.
Stratified Epithelium:
Stratified epithelia are generally resistant to damage by wear and tear because of ready replacement of cells.
Passive diffusion through these layers is low but not impossible.
Stratified squamous- these layers of cells line the skin, oral cavity, pharynx, vocal folds, esophagus, vagina and anus.
The basal cells are columnar and germinal. The outermost layers of skin epithelia cilia are fibrous like, desiccated,
non-nucleated cells containing keratin (a scleroprotein).
Transitional- multiple layers of cells lining the urinary tract. In the empty (contracted) bladder, define room muscular
layer is contracted due to resting tension of muscle cells, in the surface layer of the rounded cells is closely
concentrated, creating a bumpy surface. With distension of the bladder, all the cells stretch outfit form a smooth, thin
surface. The bladder can store volumes of urine up to 1,000 ml or so.
Glandular epithelium- glandular cells produce and secret/ materials of varying composition, sweat, milk, sebum,
cerumen, hormones, enzymes, and so on. specialized contractile epithelial cells (myoepithelial) encourage discharge
of the glandular material.
Exocrine- exocrine glands examples with sweat, pancreatic, mammary and so on arises out pocketing of epithelial
lining tissue, retain a duct to the surface of the cavity or skin, and excrete/ secrete some substances. Secretory
portions may have one of several shapes (tubular, coiled, alveolar) connected to one or more ducts.
Endocrine- endocrine glands arise as if it will yell outgrowth but lose their connection to the surface during
development. They are intimately associated with a dense capillary network and secrete their products into them.
TISSUES: EPITHELIUM
There are four basic tissues of the body: epithelial connective muscle and nervous.
Epithelial tissues (epithelium) form the body surface(skin), the surfaces of the body cavities and their contained
viscera, glands and all tubular organs, e.g., ducts and vessels.
Neuroepithelia convey sensations. Epithelia are arranged into single (simple) or several (stratified) layers. Their cells
are bound together by specialized fibers and substances (e.g., the basement membrane). Issues are generally
sensitive but avascular and receive the nutrition by diffusion.
Simple Epithelium:
Surface tissue functioning infiltration, diffusion, secretion, and absorption.
Squamous- Simple squamous it is a line the heart internal surfaces of all blood and lymph vessels and (endothelia),
the air cells of the lungs filtration capsules and theme tubules in the kidneys and the major body cavities
(mesothelia). Rapid diffusion of gases in solution or characteristic activities in these cells.
Cuboidal- simple cuboidal epithelium are generally secretory cells and makeup glands throughout the body, tubules
of the kidney, terminal bronchioles of lungs and ducts of the reproductive tracts.
Columnar- simple columnar epithelium lining the gastrointestinal tract and or concerns secretion and absorption.
There free (apical) surface may be covered with finger like projections of cell membrane called microvilli, increasing
the cell surface area for secretion/ absorption.
Pseudostratified columnar- this tissue consists of simple columnar cells together with irregularly placed nuclei giving
the appearance of multiple layers. However, each of the cells is attached to the basement membrane. This tissue
lines the of the reproductive tract and air conduction pathways of the respiratory tract. They often exhibit cilia on their
free surfaces at contain unicellular goblet shape secretory cells. The cilia collectively move surface material by virtue
of undulating power strokes.
Stratified Epithelium:
Stratified epithelia are generally resistant to damage by wear and tear because of ready replacement of cells.
Passive diffusion through these layers is low but not impossible.
Stratified squamous- these layers of cells line the skin, oral cavity, pharynx, vocal folds, esophagus, vagina and anus.
The basal cells are columnar and germinal. The outermost layers of skin epithelia cilia are fibrous like, desiccated,
non-nucleated cells containing keratin (a scleroprotein).
Transitional- multiple layers of cells lining the urinary tract. In the empty (contracted) bladder, define room muscular
layer is contracted due to resting tension of muscle cells, in the surface layer of the rounded cells is closely
concentrated, creating a bumpy surface. With distension of the bladder, all the cells stretch outfit form a smooth, thin
surface. The bladder can store volumes of urine up to 1,000 ml or so.
Glandular epithelium- glandular cells produce and secret/ materials of varying composition, sweat, milk, sebum,
cerumen, hormones, enzymes, and so on. specialized contractile epithelial cells (myoepithelial) encourage discharge
of the glandular material.
Exocrine- exocrine glands examples with sweat, pancreatic, mammary and so on arises out pocketing of epithelial
lining tissue, retain a duct to the surface of the cavity or skin, and excrete/ secrete some substances. Secretory
portions may have one of several shapes (tubular, coiled, alveolar) connected to one or more ducts.
Endocrine- endocrine glands arise as if it will yell outgrowth but lose their connection to the surface during
development. They are intimately associated with a dense capillary network and secrete their products into them.
