Ch 4: Epithelial Tissue

What are some general characteristics of epithelial tissue?

closely packed cells, little extracellular material, often found on free surfaces, adheres to basement membrane, not penetrated by blood vessels, penetrateed by nerves, rapid growth and turnover(regeneration), classified by cell shape and number of layers of cells

How do you classify epithelial tissue?

by the layers and shape of cells

What is a single layer called?

simple

What is several layers called?

stratified

What is a flat like shape called

squamous

what is a cube like shape called

cuboidal

what is a tall shape like called?

columnar

What are the types of simple epithelial linings?

Simple squamous, simple cuboidal, simple columnar, pseudostratified (ciliated)

What are the types of stratified epithelial linings?

Stratified squamous epithelium “dry”, stratified squamous epithelium “moist”, transitional epithelium

What is the function of simple squamous epithelium? What is an example?

rapid diffusion, air sacs of lungs

What is the function of simple cuboidal epithelium? What is an example?

Secretion and absorption, kidney tubules

What is the function of simple columnar epithelium? What is an example?

secretion and absorption, linings of stomach and intestines

To which simple epithelial lining do goblet cells belong to?

Simple columnar epithelium

What is the function of goblet cells?

to produce mucus

What is the function of pseudostratified epithelium? What is an example?

moving/sweeping mucus, lining of trachea & bronchi

What is the function of stratified squamous epithelium “moist”, non keratinized? What is an example?

protectoin, lining of mouth/esophogus

What is the function of stratified squamous epithelium “dry” nonkeratinized? What is an example?

protection, skin

What does keratinized mean?

water proofing protein

What is the function of transitional epithelium? What is an example?

protection + stretches, bladder

What is an exocrine gland?

glands with ducts

What is an endocrine gland?

ductless glands

What is the function of exocrine glands?

secrete a fluid to a surface

What are the 3 modes of secretion found in exocrine glands?

Merocrine, apocrine, holocrine

What is the function of merocrine? what is an eample?

secrete product to surface, sweat glands

what is the function of apocrine? What is an example?

secrete a small part of the cell to surface, milk from mammry gland or ear wax

What is a function of holocrine? What is an example?

secrete whole cells to surface, oil or sebaceous glands of skin

What is the function of endocrine glands? What is an example?

secrete messenger chemicals called hormones into the blood, where they are taken to distant “target tissues”, in which they cause profound changes, ovary→estrogen