Epithelial Connective Tissues

Question 1

What is a Tissue?

Answer 1

a group of cells of similar structure that perform a common function

Question 2

What are the 4 basic types of tissue found in the human body?

Answer 2

Epithelium
Connective tissue
Muscle Tissue
Nerve tissue

Question 3

What is epithelium?

Answer 3

a sheet of cells covering body surfaces or lining body cavities.

• they line hollow stuff too like the respiratory tract and reproductive tract
• form most of the body’s glands

Question 4

What are the functions of epithelia?

Answer 4

• form the parenchyma of many organs
• Physical protection
• forms a functional barrier between two extracellular compartments
• Sensory
• Secretory

Question 5

What are the two types of epithelia tissue?

Answer 5

• membranous epithelia

- glandular epithelia (endo and exocrine glands)

Question 6

what does parenchyma mean?

Answer 6

it means it is the functional tissue

Question 7

What are the structural features of membranous epithelium?

Answer 7

• line free surfaces including a lumen
• cells are tightly packed together
• structurally and functionally polarized
• Avascular: they must get their nutrients via diffusion
• Very well innervated
• have a high capacity to regenerate following damage

Question 8

How are epithelia classified?

Answer 8

based on the shape of their cells and the number of layers

Question 9

What are the different cell shapes of epithelial cells?

Answer 9

Squamos, cuboidal, columnar

Question 10

What are the different kinds of layers in epithelial cells?

Answer 10

Simple or stratified

Question 11

What are the different kinds of epithelia?

Answer 11

simple squamos, simple cuboidal, stratified squamos or cuboidal, simple columnar, pseudostratified columnar, stratified columnar (rare), and transitional.

Question 12

What is different about transitional epithelium?

Answer 12

it has the ability to stretch from a rounded dome-like 5-6 layers to about 3 layers of squamous cells

Question 13

What are some of the structural specializations on the apical surface of epithelial cells?

Answer 13

• Microvilli
• Stereocilia: immobile
• cilia: high mobile

Question 14

What is Kartagenar’s syndrome

Answer 14

mutation in motor protein causing cilia to lose mobility

-leads to infections and hearing loss

Question 15

What is the basement membrane?

Answer 15

a layer of extracellular matrix at the basal surface of all epithelia
-also found surrounding other groups of cells like peripheral nerves

Question 16

What produces basement membranes?

Answer 16

epithelial cells

Question 17

What attaches epithelial cells to the basement membrane?

Answer 17

hemidesmosomes

Question 18

Why do diabetics have circulation problems?

Answer 18

their basement membranes thicken overtime so the bv’s get constricted

Question 19

What are the different types of epithelial junctions?

Answer 19

• Tight: near apical end
• Intermediate: the belt thing, linked to actin filament network
• Desmosome: intermediate filaments
• Gap: important for intercellular communication. made of connexons

Question 20

What do many autoimmune diseases attack?

Answer 20

desmosomes and adherens junctions

Question 21

Epithelial cells make glands. What do they do?

Answer 21

secret ions, enzymes, and regulator peptides

Question 22

What are the two types of glands?

Answer 22

• Endocrine: secreted into blood, distributed throughout body
• Exocrine: secreted product is released onto free surface of epithelium

Question 23

Which type of gland has ducts?

Answer 23

Exocrine

Question 24

Which type of gland is Ductless?

Answer 24

endocrine

Question 25

How are all of these glands classified?

Answer 25

• Structural organization: # of cells, # of ducts, shape of glandular unit
• Type of secretion: Mucous (slimy glycoproteins), serous (water, enzymes, and ions), or seromucous