Epithelium & Glands

Question 1

What is a tissue? Composition?

Answer 1

collection of cells with usually the same characteristics and perform a specific function; composed of 2 components: cell and ECM

Question 2

Types of tissues? Differentiate accdg to components and main function.

Answer 2

Muscle, Epithelial, Nervous, Connective.
Epithelium - aggregated polyhedral cell with small amt of ECM; fxn: lining of surface or body cavities and glandular secretion

Question 3

Functions of epithelium

Answer 3

Barrier, Secretion, Absorption, Protection, Lubrication, Reproduction, Transport

Question 4

A patient with tumor goes to you. How would you know if the tumor is of epithelial origin? Why is knowing it important?

Answer 4

Check for the presence of keratin since it is the main intermediate filament of epithelial cells. It is important because different cell tumors depending on the type or origin of basic tissue respond differently to treatment.

Question 5

How does the epithelium get the proper nutrition?

Answer 5

Since it is avascular, nutrients enter through diffusion in the basement membrane.

Question 6

Does the epithelium exhibit polarity or not? Expound.

Answer 6

It does because it has the apical pole (faces a space) and the basal pole (sits on BM).

Question 7

All epithelia would rest on a ___. What does the “___” do?

Answer 7

Basement Membrane, a sheet-like structure made up of macromolecules which acts like a filter, structural support for epithelial cells, attach epithelia to underlying connective tissue, maintaining cellular functions, epithelial repair and regeneration (u can see SCs here).

Question 8

The basement membrane is made up of 2 structures which are (a) and (b).

Answer 8

(a) Basal lamina

(b) Reticular lamina

Question 9

Cell Junctions or Junctional complexes of epithelial cells?

Answer 9

A. Cell-to-cell adhesions/junctions

1. Tight junction/Zonula occludens/occluding junction
2. Zonula adherens
3. Desmosome/Macula adherens
4. Gap junction/Nexus/Communication Junction

Cell-to-ECM junctions

5. Hemidesmosome
6. Focal adhesion

Question 10

Cell-to-ECM junctions? (2) Describe and what is the TM protein?

Answer 10

Hemidesmosome

• resembles half of a desmosome and is attached to the basal area
• TM protein: Integrins

Focal adhesion

• resembles hemidesmosome but numerous and smaller
• TM protein: Integrins

Question 11

Classification of glands based on:

1. Path of release
2. Based on number of cells
3. Morphology

Answer 11

1. Path of release: endocrine
exocrine
paracrine
2. Based on no. of cells
a. unicellular
b. multicellular
3. Morphology
a. Simple/branched
b. Tubular/acinar or alveolar
c. coiled

Question 12

Only unicellular gland

Answer 12

Goblet cell

Question 13

Classification of glands based on:

1. Path of release
2. Based on number of cells
3. Morphology
4. Type of secretion
5. Gland-cell secretion

Answer 13

1. Path of release: endocrine
   exocrine
   paracrine
2. Based on no. of cells
   a. unicellular
   b. multicellular
3. Morphology
   a. Simple/compound
   b. branched
   c. Tubular/acinar or alveolar/Coiled
   d. Serous/mucous
4. Type of secretion
   a. Serous
   b. Mucous
5. Gland-cell secretion

Question 14

Only unicellular gland

Answer 14

Goblet cell

Question 15

Classification of glands based on:

1. Path of release
2. Based on number of cells
3. Morphology
4. Type of secretion
5. Gland-cell secretion

Answer 15

1. Path of release: endocrine
   exocrine
   paracrine
2. Based on no. of cells
   a. unicellular
   b. multicellular
3. Morphology
   a. Simple/compound
   b. branched
   c. Tubular/acinar or alveolar/Coiled
   d. Serous/mucous
4. Type of secretion
   a. Serous
   b. Mucous
5. Gland-cell secretion
   a. Merocrine/Eccrine
   b. Holocrine
   c. Apocrine