Sept 18 Lecture: Epithilial Tissue

Question 1

What are the four types of tissue in the body

Answer 1

Epithelial, connective, muscle, and nervous.

Question 2

In general what are tissues made of

Answer 2

They have cells that are related in structure and function, and an extra cellular matrix.

Question 3

What are the functions of the ECM

Answer 3

They provide the tissue with strength against tensile and compressive forces, they hold the cells in place, and support the function and survival of cells

Question 4

What are the two main components of the ECM

Answer 4

Ground substance and protein fibers

Question 5

What is ground substance

Answer 5

Extra cellular fluid made of water, ions, and macromolecules

Question 6

What are the protein fibers in the ECM

Answer 6

Large polypeptides that are embedded within the ground substance. They have a rope like structure and provide tensile strength

Question 7

What are the three types of protein fibers

Answer 7

Collagen fibers that resist tension and pressure, elastin fibers that allow stretch and recoil, and reticular fibers which are small collagen fibers that form a scaffold like structure to support the cells and ground substance

Question 8

What are the three types of junctions in cells

Answer 8

Tight junctions, desmosomes, and GAP junctions

Question 9

What are tight junctions

Answer 9

Junctions that leave no space in between cells

Question 10

What are desmosomes

Answer 10

Junctions that increase resistance of the tissue to mechanical stress. In other words they create strong connections

Question 11

What are Gap junctions

Answer 11

Junctions that allow small substances to move from one cell to another

Question 12

Where is the ECM found in epithelial tissues

Answer 12

The ECM is the thin layer beneath the cells called the basement membrane.

Question 13

What type of junction connects epithelial tissues

Answer 13

Desmosomes and tight junctions

Question 14

What other roles of epithelial tissue around the body

Answer 14

Protection, immune defense, secret, transportation, and sensation

Question 15

What are the two different layers of the basement membrane

Answer 15

The basil lamina- has collagen fibers and ground substance, and the reticular lamina has reticular fibers and ground substance

Question 16

How are epithelial tissues classified and name all the classifications

Answer 16

Classifications by cell layers are simple and stratified, in classifications based on the shape of the cell are squamous cuboidal and columnar

Question 17

What are the two main classifications of epithelial tissue

Answer 17

There’s covering and lining epithelia which covers every internal and external body surface, lines organs in fluid-filled cavities. Next is glandular epithelia which is a tissue that produces and secretes a product with two different types of gland

Question 18

What are the two main types of gland

Answer 18

Exocrine glands secrete substances into a duct that is lined with epithelial cells, and endocrine glands are made up of specialized epithelial cells that secrete hormones directly into the bloodstream

Question 19

What is simple squamous epithelium

Answer 19

A single layer of flat cells that allows rapid diffusion of substances like oxygen, carbon dioxide, fluids and ions

Question 20

What is simple cuboidal epithelium

Answer 20

A single layer of cube shape cells with a large Central nucleus. this is thin enough for rapid substance diffusion

Question 21

What is simple columnar epithelium

Answer 21

A single layer of rectangular shaped cells with nuclei in basal portion of cell. These cells often have microvilli (small intestine) or cilia (segments of respiratory tract) on apical plasma membrane

Question 22

What is pseudostratified columnar epithelium

Answer 22

It appears layered because nuclei are at various Heights but it is only one cell layer thick with basal plasma membranes firmly in contact with basement membrane.

Question 23

How can substances travel across simple epithelia

Answer 23

In parasellular transport substance pass between the cells and intranscellular transport substances enter the cell by active or passive means

Question 24

What is stratified squamous epithelium

Answer 24

There are two types: keratinized stratified squamous epithelium is found in the skin. The outer layers are dead and lack nuclei and it’s filled with the protein keratin which is tough and resistant to friction. The non keratinized stratified squamous epithelium has outer layers that are alive and retain their nuclei. They protect from mechanical stresses and microorganisms, and are found in the throat mouth esophagus anus and vagina.

Question 25

What is stratified cuboidal epithe

Answer 25

It lines the ducts of sweatlands

Question 26

What is stratified columnar epithelium

Answer 26

Layered epithelium where the apical layer is more columnar and the basal layer is more cuboidal. The function is protection some absorption and secretion. It’s found in the mail urethra, the cornea of the eye, and ducks of certain glands like salivary glands

Question 27

What is transitional epithelium

Answer 27

Epithelium that can expand or shrink to meet the function. There is a cuboidal basal cell layers and dome shaped applications when the tissue is relaxed and cells on the Abaco layer can flatten to allow the tissue to stretch. Found in the urinary system that lines the inside of the kidneys ureters bladder and urethra

Question 28

What type of epithelia is goblet cells

Answer 28

Glandular epithelia

Question 29

What are goblet cells

Answer 29

A single cell exocrine gland found in the epithelial layer of the digestive and respiratory tracts that secretes mucus to protect the underlying epithelium

Question 30

What are merocrine glands

Answer 30

A gland that secretes products packaged into secretory vesicles and releases them by exocytosis into ducts. Some examples are sweat glands salivary glands and exocrine pancreas

Question 31

What type of gland are most exocrine glands glands

Answer 31

Merocrine glands

Question 32

What are holocrine glands

Answer 32

They’re a type of exocrine gland that’s used by sebaceous glands in the skin and secretary cells build up products and release when the cell ruptures and dies

Question 33

What do the exocrine glands in the pancreas do

Answer 33

The secret digestive enzymes into ducts that drain into the small intestine

Question 34

What are endocrine glands in the panc

Answer 34

Endocrine gland that secrets insulin into the bloodstream