Anatomy Ch. 4

4 types of tissue

1. Epithelial 2. Connective 3. Muscle 4. Neural

4 functions of epithelial tissue

1. Provide Physical Protection 2. Control Permeability 3. Provide Sensation 4. Produce Specialized Secretions (glandular epithelium)

What are the 2 layers of Epithelia

1. simple 2. startified

What are the 3 shapes of epithelia

1. squamous 2. cuboidal 3. columnar

Simple Cuboidal Epithelium Locations

: Glands; ducts; portions of kidney tubules; thyroid gland

Epithelia are replaced by division of germinative cells (stem cells) Near basement membrane

Epithelial Maintenance and Repair

Produce secretions Onto epithelial surfaces Through *ducts* Release chemical substances through ducts to outside the body or onto another surface within the body

Exocrine glands

True or false, unicellular glands have ducts?

False

Structures that produce secretions

Glands

Attach cells to the basal lamina Half a desmosomes

Hemidesmosomes

Entire cell is lost, continual regeneration of cells

Holocrine secretion

Help cells stick together, secretions, Glycosaminoglycans

Hyaluronan (hyaluronic acid)

Secretions of Proteoglycans

Intercellular cement

Simple Cuboidal Epithelium Functions

Limited protection, secretion, absorption

Pseudostratified Ciliated Columnar Epithelium Locations

Lining of nasal cavity, trachea, and bronchi; portions of male reproductive tract

Stratified Cuboidal Epithelium Location

Lining of some ducts (rare)

Simple Columnar Epithelium Locations

Lining of stomach, intestine, gallbladder, uterine tubes, and collecting ducts of kidneys

Producing secretions in a vesicular format, and they transport the secretion to the surface of the cells, and release them by exocytosis

Merocrine secretion

Stratified Columnar Epithelium Locations

Small areas of the pharynx, epiglottis, anus, mammary glands, salivary gland ducts, and urethra

thin and flat

Squamous epithelia

several layers of cells

Stratified epithelium

Stratified Squamous Epithelium Locations

Surface of skin; lining of mouth, throat, esophagus, rectum, anus, and vagina

Why are there so many types of tissues

Tissue structure is adapted to the function of their region

Branched multicellular glands

several secretory areas sharing one duct

Epithelia is classified by ___ and ___

shape, layers

How much ___ is applied to the epithelium depends on how the transitional epithelium looks

stress/stretch

The duct structure of multicellular glands is either Simple (___) or Compound (___)

undivided-straight, divided-branched

Mucous (goblet) cells are the only ___

unicellular exocrine glands

Transitional Epithelium Locations

Urinary bladder; renal pelvis; ureters

Allow rapid communication Are held together by channel proteins (junctional proteins, connexons) Allow ions to pass Coordinate contractions in heart muscle

gap junctions

The types of secretions are based on their

method of secretion

Unicellular exocrine glands secrete ___

mucus

Layers of cells covering internal or external surfaces

Epithelia

Nonattached surface of Epithelial tissue

apical

square shaped

Cuboidal epithelia

Vesicles accumulate near the appical surface of the cell, as they gather the appical portion of the cell is pinched off, exocytosisportion of the cell is damaged and needs to regenerate

Apocrine secretion

proetins that cross cell membrane and hook to proteins of other cells, transmembrane proteins

CAMs (cell adhesion molecules)

Form bonds with other cells or extracellular material

Cell junctions

another name for mixed exocrine glands

Cerro mucinous glands

Cellularity (cell junctions) Polarity (apical and basal surfaces) Attachment (basement membrane or basal lamina) Avascularity Innervate Regeneration

Characteristics of Epithelia

Thin layer Secreted by epithelia Barrier to proteins (attachment to basement membrane)

Clear layer (lamina lucida)

tall, slender rectangles

Columnar epithelia

________ are proteins that connect adjacent cells at a gap junction

Connexins

Thick fibers Produced by connective tissue Strength and filtration (attachment to basement membrane)

Dense layer (lamina densa)

CAMs, dense areas, and intercellular cement Tie cells together, allow bending and twisting Found in small localized areas Tissues under stress i.e. skin

Desmosomes

Release hormones Into interstitial fluid No ducts Release chemical substances directly into the bloodstream or tissues of the body; surrounding tissue

Endocrine glands

Simple Squamous Epithelium Locations

Mesothelia lining ventral body cavities; endothelia lining heart; and blood vessels; portions of kidney tubules (thin sections of nephron loops); inner lining of cornea; alveoli of lungs

Both serous and mucous

Mixed exocrine glands

Thick ,slippery, secrete mucins

Mucous glands

Transitional Epithelium Functions

Permits expansion and recoil after stretching

Stratified Columnar Epithelium Functions

Protection

Simple Columnar Epithelium Functions

Protection, secretion, absorption

Stratified Cuboidal Epithelium Function

Protection, secretion, absorption

Pseudostratified Ciliated Columnar Epithelium Functions

Protection, secretion, move mucus with cilia

Stratified Squamous Epithelium Functions

Provides physical protection against abrasion, pathogens, and chemical attack

Made up on a single layer of cells, all cells reach the basement membrane

Pseudostratified

Simple Squamous Epithelium Functions

Reduces friction; controls vessel permeability; performs; absorption and secretion

Thin, watery secretions, enzyme rich

Serous glands

3 exocrine glands

Serous, Mucous, Mixed exocrine

single layer of cells

Simple epithelium

Attached surface of Epithelial tissue

basal

Germinative cells

divide continually to produce new epithelial cells

The tissue that always has an apical and a basal surface is ________ tissue.

epithelial

Pseudo

false

Glands that secrete their product by the bursting of cells are ________ glands

holocrine

The basal layer is broken up into two parts the ___ (closer to the epithelium), and the ___ (closer to the connective tissue)

lamina lucida, lamina densa

the body's most delicate type of epithelium is

simple squamous

Between two plasma membranes Adhesion belt attaches to terminal web Prevents passage of water and solutes (water tight barrier) Isolates wastes in the lumen Made up of row proteins within one cell membrane that line up with adjacent row proteins thus limiting intercellular movement

tight junctions

Are collections of cells and cell products that perform specific, limited functions

tissue

For multishaped cells, whichever cell shape is on the ___ determines its shape type

top/closest to the surface

The shape of secretory portion of the f multicellular glands is either Tubular (___) or Alveolar/acinar (___)

tube shaped, round blind pockets