Epithelium

Question 1

Epithelial tissues can be found

Answer 1

Outer body surfaces 
Lining internal cavities
Secretory portion ofnfkands and ducts
Receptors for special senses
Form glands

Question 2

Characteristics if epithelial tissues?

Answer 2

Avascular. Nourished from blood vessels in basement membrane
Exhibit polarity
Closely held together. Very little intercellylar space
Interact with a basement membrane
Capable of regeneration

Question 3

What is a basement membrane?

Answer 3

Basement membrane definition is - a thin membranous layer of connective tissue that separates a layer of epithelial cells from the underlying lamina propia.

Question 4

Which protein drives ciliary movement

Answer 4

Dynein

Question 5

Katageners syndrome?

Answer 5

Immotile cilia syndrome

Question 6

Functions of stereocilia?

Answer 6

Mechanisenseing organelles if sensory hair cells of inner ehar, and absorption. Found in epidydymis too

Question 7

What is celiac sprue?

Answer 7

Arrises from sensitivity to gluten. Leads to loss of microvilli of surface epithelium of small intestine. Reduced absorptive capacity

Question 8

Junctional complex?

Answer 8

It is an intercellular attachment structure

Question 9

Which proteins form a belt around adjacent cells in tight junctions

Answer 9

Occludin and claudin

Question 10

Where are tight junctions found

Answer 10

Blood brain barriers, blood tests barriers, csf brain barrier.

Also, many pathogenic agents acts on ZO-1 and ZO-2 causing the junction to become permeable

Question 11

Types of junctions

Answer 11

Occluding junctions
Adhering junctions
Communicating junctions

Question 12

Macula adherens…Desmosomes interact with

Zonula adherenes

Answer 12

Intermediate filaments

Actin filaments

Question 13

Hemisdesmosomes diseases

Answer 13

Epidermolysis Bullosa

Question 14

General functions of epithelial tissues

Answer 14

Absorption(columnar epithelium of intestines and proximal c t of kidney)
Secretion (columnar epithelium of stomach and gastric glands)
Protection (skin)
receptor function(taste buds, olfactory epithelium, retina of the eye)
Transportation

Question 15

What are endothelium and endocardium and mesothelium

Answer 15

1. Epithelial lining of blood and lymphatic vessels
2. Epithelial lining if ventricles and atria of the egart
3. Epithelium that lines the walls and covers contents of the closed cavities if the body. Abdominal, pericardial and pleural cavities.

Simple squamous epithelium except post capillary venules if certain lymphatic tissues which are cubical. Called high endothelial venules

Question 16

Simple cuboidal function and location

Answer 16

Secretion

ovary, thyroid

Question 17

Simple columnar functions

Answer 17

Protection, lubrication, absorption and secretion

Found in lining of intestines and gall bladder

Question 18

Stratified squamous types

Answer 18

Keratinized(epidermis)  prevents water loss and secretion
Non keratinized (mouth, oesophagus, larynx, vagina, an al canal)

Question 19

Stratified cuboidal function

Answer 19

Protextyon and secretion

Swear glands and developing ovarian follicles

Question 20

Stratified columnar function

Answer 20

Protection

Conjunctiva

Question 21

Psuedostrtified

Answer 21

For protection and secretion

Trachea, bronchi and nasal cavity

Question 22

Pseudostatifies cells are usually found in

Answer 22

Mucous secreting cells with goblet cells and cilia

Question 23

Transitional epithelium is also known as

Answer 23

Urothelium

Question 24

What is transitional epithelium?

Answer 24

Stratified epithelium which has special morphological characteristics
Functionally accommodate well to distensions m
Upper cells are large, round with darkly stained cytoplasm
Function is protection and distensibility

Found in the lower urinary tract(minor calcyes of kidney to proximal part of urethra)

Question 25

Under abnormal conditions, one type of epithelial tissue can undergo transformation into another type. Process known as

Answer 25

Metaplasia Eg: in heavy cigarette smoke, ciliated pseudostratified epithelium can be stratified squamous epithelium

Question 26

Barrett's Oesophagus

Answer 26

!!

Question 27

What are parenchyma and stroma

Answer 27

Secretory units and the ducts Connective tissue that invade and support the parenchymaq

Question 28

What is signalling?

Answer 28

Substances being produced interact with proteins and receptors and activate it to involve in a particular function

Question 29

Only unicellular glands in mammals are

Answer 29

Goblet cells

Question 30

Classification of glands based on mode of secretion

Answer 30

Merocrine: secretion via exocytosis(parotid gland) Apocrine: portion of apical cytoplasm released with product (lactating mammary gland) Secretory cell matures and dies and becomes the secretory product. Sebaceous gland

Question 31

Classification of glands based on nature of substances produced?

Answer 31

Mucous glands Secrete mucinogen. Large glycosykated proteins which upon hydration swell to become a thick viscous gel. P Brunners gland and goblet cell Serious gland produce enzyme rich fluid Examoles pancreas, parotid, paneth cells, chief cells of gastric glands Mixed Salivary glands eg submandibular

Question 32

Slide 57

Answer 32

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