Anatomy 9 - Epithelia Flashcards Preview

Second Year - Anatomy CA21007 > Anatomy 9 - Epithelia > Flashcards

Flashcards in Anatomy 9 - Epithelia Deck (38)
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1
Q

What is epithelia composed of

A

Closely aggregated, polyhedral epithelial cells with a minimum of intercellular substance

2
Q

Adhesion between epithelia is

A

Strong

3
Q

What is epithelia able to cover

A

Exposed external surface and internal cavities

4
Q

Common features of epithelia

A

Usually polarised, have a sheet like structure at their basal surface composed of extracellular matrix called the basal lamina, nearly all are non-vascular and they tend to bind together in sheets

5
Q

Surface epithelia

A

Cover or line surfaces, cavities and tubes

6
Q

What are epithelial tissues derived from

A

All of the embryological germ layers: ectoderm, endoderm and mesoderm

7
Q

Functions of epithelia

A

Mechanical barrier, chemical barrier, adsorption, secretion, containment, locomotion by cilia, sensation and contractility

8
Q

Example of mechanical barrier epithelium

A

Skin

9
Q

Example of chemical barrier epithelia

A

Lining of the stomach

10
Q

Example of adsorption epithelia

A

Lining of the intestine

11
Q

Example of secretion epithelia

A

Salivary gland

12
Q

Example of containment epithelia

A

Lining of urinary bladder

13
Q

Example of locomotion by cilia epithelia

A

Oviduct

14
Q

Example of sensation epithelia

A

Taste buds

15
Q

Example of contractile epithelia

A

Myoephithelial cells

16
Q

Function of cytoskeleton

A

To maintain cellular integrity

17
Q

Three main classes of filaments in the cytoskeleton

A

Microfilamnets, intermediate filaments and microtubules

18
Q

What is the function of the filamentous proteins

A

They become attached to cell membranes and to each other by anchoring and joining proteins to form a dynamic 3D internal scaffolding in the cell

19
Q

What are microfilaments composed of

A

The protein actin

20
Q

Functions of microfilaments

A

Anchorage, movement and extension of the cell membrane

21
Q

Function of intermediate filaments

A

They bind intercellular elements together and to the plasmalemma

22
Q

What are microtubules made up of

A

The two tubulin subunits, alpha and beta

23
Q

Functions of microtubules

A

Move components of the cell

24
Q

What are intercellular junctions

A

Specialised membrane structures which link individual cells together into a functional unit

25
Q

What are the three types of membrane junctions

A

Occluding junctions, anchoring junctions and communicating junctions

26
Q

What are occluding junctions

A

They link cells to form a diffusion barrier

27
Q

What are anchoring junctions

A

They provide mechanical strength

28
Q

What are communicating junctions

A

Allow movement of molecules between cells

29
Q

What is linked together in anchoring junction

A

Submembrane actin bundles

30
Q

If the outer layer of adjacent cells appear fused it is known as

A

A pentalaminar structure

31
Q

What are desmosomes

A

They lin k submembrane intermediaries filaments of adjacent cells

32
Q

What do desmosomes provide

A

Mechanical stability

33
Q

What is found in the cell membranes of communicating junction cells

A

Several hundred pores

34
Q

What are epithelia classified by

A

Cell shape, number of layers of cells, cell surface specialisation and the presence of any specialised cell type

35
Q

What are the different cell shapes

A

Squamous, cuboidal and columnar

36
Q

What are the different number of layers of cells called

A

Simple - one layer
Stratified - two or more layers
Pseudostratified - tissue appears to have multiple layers, but in fact all cells are in contact with the basal lamina

37
Q

What are the cell surface specialisation categories

A

Prominent microvilli, cilia and keratinised

38
Q

What specialised cells can be present in epithelia

A

Goblet cells