Tissues 1

Question 1

What are the properties of epithelial tissues

Answer 1

• Covers surfaces
• Cells connected
• Separates compartments
• Cells define compartments
• Has a diversity of secondary functions
• Forms glands

Question 2

What are properties of connective tissue?

Answer 2

• It connects
• Consists of few cells in extracellular matrix and fluid
• Varies from Liquid to solid

Question 3

Give three examples of connective tissue

Answer 3

Blood
Bone
Adipose

Question 4

What is the function and features of connective tissues?

Answer 4

• Long thin cells
• Contractile
• Cytoplasm packed with contractile apparatus
• Shortens lengths,
• Closes down spaces

Question 5

What are the categories of muscle tissue

Answer 5

Skeletel
Smooth
Cardiac

Question 6

What is the stretch of each muscle tissue

Answer 6

Skeletal & cardiac-Limited

Smooth- can stretch

Question 7

What is nervous tissue important for?

Answer 7

Important in communication

Question 8

What does nervous tissue consist of?

Answer 8

neurones and support cells (glee)

Question 9

What does nervous tissue do?

Answer 9

• Receives, generates and transmits electrical signals

- Integrates information from around the body

Question 10

What are the histological features of skeletal muscle?

Answer 10

• striated
• highly ordered arrangement of contractile proteins
• multiple nuclei per cell

Question 11

What are the histological features of cardiac muscle?

Answer 11

• striated
• highly ordered arrangement of contractile proteins
• single nuclei per cell

Question 12

What are the histological features of smooth muscle?

Answer 12

• non-stirated (smooth)

- less ordered arrangement of contractile protein

Question 13

What do motor neurones consist of?

Answer 13

-cell body(soma)
-dendrites on cell body and terminal
axon and terminals

Question 14

What do sensory neurones consist of?

Answer 14

• cell body at side of axon
• dendrites and receptor and terminal
• axon

Question 15

Plasma membrane involved in what in nerve physiology

Answer 15

generation and conduction of action potentials

Question 16

Endothelium

Answer 16

refers to cells that line the inside of blood vessels

N.B this is technically not just a type of epithelium as has vimentin not keratin

Question 17

How does epithelial tissue maintain coverage of surfaces?

Answer 17

• Contact inhibition
• strong Cell-cell junctions allow them to stick together
• strong Cell-ECM junctions

Question 18

what is a desmosome?

Answer 18

a cell-cell junction in which which cells stick together by a plaque of protein and filamentous proteins radiate out.

Question 19

What is the purpose of a desmosome?

Answer 19

Firm anchorage

Question 20

What type of junction is a desmosome?

Answer 20

cell-cell junction

Question 21

What causes some desmosomes to be less strong than others?

Answer 21

some desmosomes lack plaque protein in centre

Question 22

what type of junction is a tight junction?

Answer 22

cell-cell junction

Question 23

what are desmosomes also know as?

Answer 23

adhering junctions or macula adherens

Question 24

What is the function of a tight junction?

Answer 24

seals intercellular spaces

- prevents liquids leaking out or in

Question 25

What is the tight junction also known as?

Answer 25

occluding junctions

Question 26

What function do tight junctions serve in intestine?

Answer 26

seals intercellular junction between villus, preventing leak of digestive enzymes and bacteria into blood

Question 27

what type of junction is a gap junction

Answer 27

A cell-cell junction

Question 28

what is the function of a gap junction?

Answer 28

Cell to cell communication

Question 29

what is another term for gap junction?

Answer 29

communicating junction and nexus

Question 30

How do gap junctions allow for communication?

Answer 30

Holes in the membrane allow for the movement of small molecules (e.g. Calcium ion) which are involved in singling

Question 31

What its an example of a gap junction?

Answer 31

cardiac muscle-due to gap junctions all heart muscle contracts together

Question 32

What is the basement membrane composed of?

Answer 32

Basal Lamina, which sits on top of Reticular Lamina

Question 33

What is a Hemidesmosomes

Answer 33

Half a desmosome | connecting epithelial cells to basal Lamina

Question 34

Cell-ECM junctions

Answer 34

- Skin to basal lamina - Blood vessel endothelium to basal lamina - both use hemidesmosomes

Question 35

Secondary roles of endothelium

Answer 35

- Thick to resist wear and tear (e.g. skin) - Thin to allow diffusion (e. g. lining of alveoli or "endothelium of blood vessels"-technically not epithelium) - Movement:Cilia - Absorption:microvili

Question 36

What are cilia ?

Answer 36

Finger like projections from the apical surface involved in movement

Question 37

What does the apical surface face?

Answer 37

lumen or external environment

Question 38

what does basal surface face ?

Answer 38

basement membrane

Question 39

what is cilia made of?

Answer 39

9+2 arraignment of microtubules (made of tubulin) to give movement

Question 40

how many cilia are there per cell?

Answer 40

100s

Question 41

dimensions of a cilium

Answer 41

5-10 x 0.2 microns

Question 42

where would cilia be found?

Answer 42

e.g. trachea

Question 43

What are microvilli?

Answer 43

finger like projections from apical surface involved in absorption or secretion

Question 44

dimensions of microvilli

Answer 44

0.5x <0.1 microns (smaller than cilia)

Question 45

where would microvilli be found?

Answer 45

in small intestine on villus

Question 46

what are microvilli made of

Answer 46

actin cytoskeleton +spectrin cross links

Question 47

What is epithelial tissue good at

Answer 47

``` adaptive power (e.g. epidermal stem cells) reiterative power e.g. after skin cut ```

Question 48

What does the function of epithelial tissue depend on

Answer 48

the cells and not the extracellular matrix

Question 49

What is simple epithelia?

Answer 49

one cell thick

Question 50

what is stratified epithelia?

Answer 50

multiple cells thick

Question 51

what is Squamous epithelia?

Answer 51

thin layer

Question 52

What lines the mouth and blood vessels?

Answer 52

Simple Squamous epithelium

Question 53

what is cuboidal epithelia?

Answer 53

roughly cube-like, similar width as height as depth

Question 54

what is columnar epithelia?

Answer 54

noticeably more long than wide

Question 55

lining of gut and ovary is (....) epithelium

Answer 55

Columnar epithelium

Question 56

What epithelial tissue is skin made of?

Answer 56

Stratified Squamous epithelia with stem cells at Bottom and keratin at top.

Question 57

what epithelial tissue lines Salivary gland?

Answer 57

Stratified Cuboidal and Columnar

Question 58

what are stratified transitional epithelium? and what are there functions

Answer 58

AN epithelia that: only lines the bladder and most of urinary tract (some portions of urethra not lined) - round - flexible as bladder stretches a lot - protective and impermeant to urine and its toxins

Question 59

What are Pseudostratified c(olumnar) epithelium

Answer 59

Not stratified but appears stratified, with all cells touching basement membrane and hence cells all having different shapes. The trachea for example has pseudostratified (columnar) epithelium NB. rarely occurs in cuboidal or squamous tissue.