TOB L1.2 EPITHELIAL TISSUES Flashcards

1
Q

Simple Squamous Epithelia

Locations (6 points)

A
  • Lining of blood vessels “endothelium”
  • Lining of body cavities - pericardium, pleura, pertoneum ‘mesothelium’
  • Respiratory epithelium (pulmonary alveoli)
  • Bowman’s capsule (kidney)
  • Loop of Henle (kidney)
  • Inner and middle ear
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Simple Squamous Epithelia
Functions
(LGBaT)

A
  • Lubrication (pericardium, pleua, peritoneum/viscera)
  • Gas exchange (alveoli)
  • Barrier (bowmans capsule)
  • Active transport via pinocytosis (meso/endothelium)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Simple Cuboidal Epithelia

Locations (four)

A
  • Thyroid follicles
  • Small ducts of many exocrine glands
  • Kidney tubules
  • Surface of the ovary (germial epithelium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Simple Cuboidal Epithelia - It’s glandular!
Functions (four)
Baah(riatric)

A
  • Barrier/covering (ovary)
  • Absorption & Conduit (exocrine glands)
  • Absorption & Secretion (kidney tubules)
  • Hormone synthesis, storage and metabolism (thyroid)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Simple Columnar Epithelia

Locations (seven)

A
  • Stomach lining & gastric pits
  • Small intestine &olon
  • Gall bladder
  • Large ducts of some exocrine glands
  • Uterus
  • Oviducts
  • Ductuli efferents of testis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Simple Columnar Epithelia
Functions (four)
LAST

A
  • Lubrication (small intestine & colon)
  • Absorption (small intestine, colon & gall bladder)
  • Secretion (stomach lining & gastric pits, small intestine & colon)
  • Transport (oviduct)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

(simple) Pseudostratified Epithelia

Locations (five)

A
  • Lining of nasal cavity, trachea and bronchi
  • Epididymis and ductus deferens
  • Auditory tube and part of typanic cavity
  • Lacrimal sac
  • Large excretory ducts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

(simple) Pseudostratified Epithelia
Functions (four)
MAPS

A
  • Mucus secretion (Nasal Cavity, trachea and bronchi (URT) )
  • Absorption (Epdidiymis)
  • Particle trapping and removal (URT)
  • Secretion and conduit (URT, ductus deferens)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Stratified Squamous Non-Keratinised Epithelia

Locations (seven)

A
  • Oral cavity
  • Oesophagus
  • Larynx
  • Vagina
  • Part of anal canal
  • Surface of cornea
  • inner surface of eyelid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Stratified Squamous Non-Keratinised Epithelia

Functions (two)

A
  • Protections against abrasion

- Reduces water loss whilst remaining moist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Stratified Squamous Keratinised Epithelia

Locations (two)

A
  • Surface of skin

- Limited distribution in oral cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Stratified Squamous Keratinised Epithelia

Functions (four)

A
  • Protection against abrasion
  • Prevents water loss
  • Prevents ingress of microbes
  • Shields against UV light damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q
Stratified Transitional (urinary) Epithelia
Locations (four)
A
  • Renal calyces
  • Ureters
  • Bladder
  • Urethera
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
Stratified Transitional (urinary) Epithelia
Functions (two)
A
  • distensibility

- protection of underlying tissue from toxic chemicals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Basement membrane

Position + Description

A

Thin, flexible, acellular layer which lies between epithelial cells and subtending connecting tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Basement membrane

Structure

A
  • Basal lamia, laid down by epithelial cells
  • Thickness increased by a variably thick layer of reticular fibrils (type 3 collagen), elaborated by subtrending connective tissue
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Basement Membrane

Function (three)

A
  • Strong, flexible layer to which epithelial cells adhere
  • Serves as cellular and molecular filter
  • Degree to which malignant cells penetrate basmenent membrane highly relevant to prognosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Defintion of Epithelial tissue

A

Sheets of contiguous cells, of varied embryonic origin, that cover the external and internal surfaces of the body

19
Q

Describe rate of renewal in epithelial tissue

A
  • High rate of renewal
  • Differs depending on type and function
  • Constant rate unless accelerated by damage
  • In skin, time from differentiation, migratiion to exterior, keritnization and death 28 days.
20
Q

State the meaning of the term tissue

A

A collection of cells specialised to perform a particular function. Aggregation of tissues constitutes organs.

21
Q

Define histology

A

The study of the structure of tissues by means of special staining techniques combined with light and electron microscopy

22
Q

Why is histology important to doctors?

A

Many diseases, such as chron’s or cancer, doctors will not give a treatment until histopathologists have given a diagnosis.

23
Q

How big are most cells?

A

10-20 micrometers

24
Q

What is a smear and what tissues can it be used on?

A

Collect cells by spontaneous/mechanical exfoliation and smeared on slide.
Cervix or the buccal cavity

25
Q

What is a curettage and what tissues can it be used on?

A

Remove tissue by scooping/scraping

Endometrial lining of uterus

26
Q

What is a needle biopsy and what tissues can it be used on?

A

Put into tissues to gather cells

Brain, breast, liver, kidney, muscle

27
Q

What is a direct incision and what tissues can it be used on?

A

Cut directly into tissues of interest and remove tissue

Skin, mouth, larynx

28
Q

What is endoscopy and what tissues can it be used on?

A

Removal of tissues via intruments through an endoscope

Lung, intestine, bladder

29
Q

What is transvascular and what tissues can it be used on?

A

Tissue taken from blood vessels

Heart, liver

30
Q

Give two fixatives

A

Glutaraldehyde and formaldehyde

31
Q

What do fixatives do on a cellular level?

A

Form covalent bonds between free amino groups of proteins, cross lining adjacent proteins. This arrests biological activity, preventing autolysis and putrefaction and makes cells more ammenable to staining and rendering them more stable.

32
Q

What is a shrinkage artifact and how can it be caused?

A

Abnormalities in slide, caused by tissue dehydration and re-hydration in slide preparation process.

33
Q

What does Haematoxylin stain, and what colour? Is haemotoxylin basic or acidic?

A

Acidic components of cell, such as Nucelolus (RNA), Chromatin (DNA). Stains them purple/blue. Haemotoxylin is basic.

34
Q

What does Eosin stain, and what colour? Is Eosin basic or acidic?

A

Stains basic components of cells, such as cytoplasmic proteins and extracellular fibres. Stains them pink. Eosin is acidic.

35
Q

What is PAS?

A

Period Acid-Schiff

Stains carbohydrates and glycoproteins magenta.

36
Q

What is Phase contrast microscopy, and what are its advantages?

A

Uses interference effects of two comibining light waves

Enhances the image of unstained cells

37
Q

What is dark field microscopy, and what are its advantages?

A

Exclude unscattered beam (light/electron) from the image.

Good with live and unstained samples

38
Q

What is fluorescent microscopy, and what what are its advantages?

A

Target molecule of interest with fluorescent antibodies

Use multiple different fluorescent stains on one specimen

39
Q

What is confocal microscopy, and what are its advantages?

A

Tissue labelled with one or more fluorescent probes
Eliminates “out of focus flare”,
Allows 3d imaging from a series of 2D images
Allows imaging of living specimens.

40
Q

Define epithelial cells

A

Sheets of contiguous cells, of caried embryonic origin that cover the external surface of the body and line internal surfaces

41
Q

What is the function of microvilli occludin?

A

Bind adjacent plasma membranes tight together in the apical portions of some epithelia.
This means membrane proteins cannot bypass zonula occluden, so cell is able to restrict certain proteins to its apical surface and segregate other to its lateral basal surfaces.

42
Q

Define microvili

A

Apical extensions that greatly increase the surface area for selective absoption of intestinal contenes

43
Q

Define stereocillia

A

Very long microvili extrend from surface of ductus deferens and the epididymis. May have an absorptive function.

44
Q

Define cillia

A

Extensions from cells which beat in coordinated waves. Found in the lining of trachea where they sweep mucus and dirt out of liungs. Also found in fallopian tubes, where they move the ovum from the ovary.