Tissues

Question 1

what is the general function of epithelial tissue? (4)

Answer 1

• cover surfaces
• connect cells
• separate compartments
• attach to basal membrane

Question 2

what does the basal membrane consist of?

Answer 2

basal lamina and reticular lamina

Question 3

what is the structure of cilia?

Answer 3

• projections from apical surface

- formed form tubulin (9+2 arrangement)

Question 4

what are the similarities and differences between cilia and microvilli?

Answer 4

similarities:
- both projections from apical surface
differences:
- microvilli shorter and thinner than cilia
- microvilli supported by actin cytoskeleton and spectrin cross links

Question 5

what are the types of classification for epithelial cells?

Answer 5

SIMPLE: 
- squamous
- cuboidal 
- columnar 
STRATIFIED: 
- squamous 
- cuboidal 
- columnar 
- transitional 
PSEUDOSTRATIFIED COLUMNAR

Question 6

what types of exocrine glands are there? (3)

Answer 6

• tubular
• acinar
• tubuloacinar

Question 7

what is the function of exocrine glands?

Answer 7

to secrete directly onto surfaces or spaces (usually via ducts)

Question 8

what do mucous glands secrete?

Answer 8

seceretions rich in proteoglycans

Question 9

what do serous glands secrete?

Answer 9

watery protein rich secretions

Question 10

what are myoepithelial cells?

Answer 10

epithelial cells that have differentiated into muscle cells

- these surrond exocrine glands and contract to force the secretions out

Question 11

what do endocrine glands secrete?

Answer 11

proteinaceous secretions

- e.g peptide or steroid hormones

Question 12

where do endocrine glands secrete?

Answer 12

dircetly into the bloodstream

Question 13

how are steroid hormones stored?

Answer 13

stored as a lipid precursor in a lipid droplet

Question 14

why are steroids stored as lipid precursors?

Answer 14

steroid hormones can travel directly through cell membrabes

Question 15

which gland secretes steroid hormones?

Answer 15

adrenal gland

Question 16

what type of epithelial cells are found in the liver?

Answer 16

hepatocytes

Question 17

what structure do epithelial cells in the kidneys form?

Answer 17

nephrons

Question 18

what is the parenchyma of an organ?

Answer 18

the main bulk of the organ

Question 19

what can cause abnormal function of glands?

Answer 19

• under/ over proliferation
• under/over secretion
• loss of cilia
• loss of ciliary beat

Question 20

what types of tissue are included as connective tissue?

Answer 20

• blood
• mucus
• cartilage
• bone
• adipose

Question 21

what properties does collagen have? (3)

Answer 21

• high tensile strength
• flexible
• inelastic

Question 22

which cells produce collagen?

Answer 22

fibroblasts

Question 23

how many types of collagen are there?

Answer 23

19+

Question 24

how do collagen fibres form?

Answer 24

1. polypeptides fold to form a triple helix
2. these helices twist together to form a microfibril
3. these microfibrils then join together to form a fibril
4. the fibril goes on the form a collagen fibre

Question 25

where would type 1 collagen be found?

Answer 25

tendons

Question 26

where would type 4 collagen be found?

Answer 26

in the basal lamina (reticulin)

Question 27

what are elastic fibres formed from?

Answer 27

fibrin and elastin

Question 28

what properties do elastic fibres have?

Answer 28

- can stretch 1.5 times and return to original shape - have a yellow colour - form flat sheets

Question 29

what does extracellular matrix consist of? (3)

Answer 29

- glycoproteins (laminin and fibronectin) - tissue fluid - ground substance

Question 30

what does ground substnace consist of?

Answer 30

- proteoglycans (protein core and GAGS) | - hyaluronic acid

Question 31

what are proteoglycans?

Answer 31

carbohydrate rich chains

Question 32

what cells are permanent loose conncetive tissue? (5)

Answer 32

- fibroblasts - macrophages - adipocytes - mast cells - undifferentiated meshenchyme cells

Question 33

what cells are transient loose conncetive tissue?

Answer 33

white blood cells

Question 34

what structure does dense regular conncetive tissue have?

Answer 34

collagen bundles aligned in one direction with parallel orientations

Question 35

give an exmaple of dense regular conncetive tissue

Answer 35

tendons

Question 36

what structure does dense irregular connective tissue have?

Answer 36

bundles arranged in a 3-D shape, allowing force from all directions to be applied

Question 37

give an example of dense irregular tissue

Answer 37

skin (dermis)

Question 38

where would you find simple squamous epitheial tissue?

Answer 38

the lining of all vascular elements e.g lining of arteries

Question 39

where would you find simple cuboidal epithelial tissue?

Answer 39

in the ducts of many glands

Question 40

where would you find simple columnar epithelial tissue?

Answer 40

the lining of the gut and larger ducts of exocrine glands

Question 41

where would you find stratified squamous epithelial tissue?

Answer 41

buccal mucose, pharynx, larynx

Question 42

where would you find stratified transitional epithelial tissue?

Answer 42

the urinary bladder and urethra