Lab 1: Epithelium

four main tissues

epithelium

connective tissue

muscle

nervous tissue

Ubiquitous tissue

epithelium

found everywhere

epithelium…

covers surfaces

lines cavities

forms glands

Does epithelium have a basement membrane?

yes, with connective tissue underneath

What may be found on the apical surface (free side) of epithelium?

cilia - motile process

microvilli - short finger-like projections

stereocilia - long microvilli

cilia

motile process

apical surface

microvilli

short finger-like projections

apical surface

stereocilia

long microvilli

apical surface

psuedostratified columnar epithelium

looks multilayered, but it’s not

nuclei are at different levels

all cells are attached to the basement membrane

transitional epithelium

only found in the urinary system

stratified

cells change based on fluid pressure

• empty urinary bladder → cells become domed

  • full urinary bladder → cells become flat

simple epithelium locations

line the heart

blood and lymphatic vessels

pleura/pericardial/abdominal cavities

secretory units of glands

line stomach and intestines

line portions of the respiratory tract

every cell touches the basement membrane

types of simple epithelium

simple squamous

simple cuboidal

simple columnar

psuedostratified columnar

stratified epithelium locations

mouth

esophagus

larynx

epidermis (skin)

vagina

anal canal

urinary tract - transitional epithelium only

bottom layer of cells touches the basement membrane

stratified epithelium types

nonkeratinized stratified squamous

keratinized stratified squamous

stratified cuboidal

stratified columnar

transitional

simple squamous

simple columnar

simple cuboidal

psuedostratified columnar

stratified squamous (nonkeratinized)

bistratified cuboidal

stratified columnar

transitional (unstretched)

transitional (stretched)

simple squamous (feline vena cava)

simple squamous (porcine bowman’s capsule)

simple squamous (feline lung)

simple squamous (porcine pulmonary artery)

simple cuboidal (porcine medulla renal tubules)

simple columnar (canine stomach inner mucosal lining)

simple columnar (canine jejunum)

psuedostratified columnar (feline lung)

non-keratinized stratified squamous (feline oral mucosa)

keratinized stratified squamous (feline haired skin)

stratified cuboidal (porcine esophagus)

transitional (canine urinary bladder)

What tissue is located at the lining of the Bowman’s capsule and the inner lining of blood vessels?

simple squamous epithelium

What tissue type is located along the inner lining of the trachea and bronchi?

psuedostratified columnar

What tissue is found on the surface of the epiglottis?

non-keratinized stratified squamous

What tissue type is found as skin?

keratinized stratified squamous

What tissue type makes up the esophageal gland?

stratified cuboidal

What tissue is only found in the urinary bladder lining?

transitional