Epithelial Tissues Flashcards

Flashcards about Epithelial Tissues, covering cell junctions, types, structures, and functions.

What is the main function of body tissues?

Groups of similar cells working together for a specific function.

Name three types of lateral connections found in cells.

Desmosomes, Gap junctions, and Tight junctions.

What is the primary function of tight junctions?

To create a seal by fusing plasma membranes together with proteins, preventing molecule passage.

What is the function of gap junctions?

To allow sharing of substances and signals between cells through linking tunnels.

How do desmosomes prevent cells from being pulled apart?

By linking plaques of protein on plasma membranes with intermediate filaments.

Define histology and biopsy.

Histology is the study of tissues, while biopsy is sampling tissues to study potential abnormalities.

List the four basic tissue types in the body.

Nervous, Muscle, Epithelial, and Connective tissue.

What is the primary function of epithelial tissue?

Forms boundaries between different environments, protects, secretes, absorbs, and filters.

Where is epithelial tissue located?

Covers all body and organs, internally and externally.

Describe the structure of epithelial tissue regarding cell arrangement and blood supply.

Cells fit closely together in continuous sheets, have one unattached surface, rest on a basement membrane, and have no independent blood supply.

List four functions of epithelial tissue.

Protection, Absorption, Filtration, Secretion, and Sensory reception.

What is the function of microvilli?

To increase surface area for absorption and secretion.

What is the function of cilia, and what inhibits it?

Cilia project from the plasma membrane and are inhibited by nicotine, also implicated in male infertility & respiratory issues

What is the basal lamina made of, and what is its function?

Non-cellular, adhesive sheet of glycoproteins secreted between epithelial cells and connective tissue. It acts as filters and scaffolds.

How are epithelia classified?

By number of layers and cell shape.

Name the different shapes of epithelial cells.

Squamous (flattened), Cuboidal (cubes), and Columnar (tall rectangles).

What are the characteristics and functions of simple squamous epithelium?

Thin, for filtration or rapid diffusion. Found in lungs and capillaries.

Where is simple cuboidal epithelium commonly found?

In glands and ducts, walls of kidney tubules, and ovaries.

What is the function of goblet cells in simple columnar epithelium?

Produce lubricating mucus.

What is the function of pseudostratified ciliated columnar cells, and where are they found?

They line the respiratory tract and sweep away debris trapped by mucus.

What is the primary function of stratified epithelium?

Protection.

Where is stratified squamous epithelium commonly found?

On sites that deal with lots of contact or friction.

Where are stratified cuboidal and stratified columnar epithelium found?

In ducts of large glands; both types are relatively rare.

Where is transitional epithelium found, and what is its function?

Lining of urinary bladder, ureters, part of urethra. Allows for considerable stretching.

What is a gland?

Cells that make and secrete a particular product called a secretion.

How are endocrine glands different from exocrine glands?

Endocrine glands have no ducts and secrete hormones directly into blood vessels, while exocrine glands secrete through ducts to an epithelial surface.