TOB CL3 Connective Tissues

Question 1

State the three class of the connective tissues and the types in each class

Answer 1

Embryonic - mesenchymal, mucous
Proper - loose, dense irregular, dense regular
with special properties - elastic tissue, adipose tissue, reticular tissue, hematopoietic tissue, cartilage, bone

Question 2

Mesenchymal CT
Function, location (2)

Answer 2

embryonic precursor
throughout vertebrate embryo
- neural crest - head & neck
- mesoderm - rest of the body

Question 3

Mucous CT
Function

Answer 3

support & protect structures from pressure

Question 4

Loose CT
Function, location

Answer 4

elasticity, flexibility, support under pressure & low friction
beneath epithelial layer

Question 5

Dense irregular CT
Features, function, location

Answer 5

fibroblast + thick collagen fibres, irregular orientation (thickness & length)
provide strength, resistant to stress
periosteum of bone, joint capsules, dermis

Question 6

Dense regular CT
Features, function, location

Answer 6

fibroblast + parallel collagen fibres
strong attachment
tendon, ligament

Question 7

Reticular CT
Features, function, location

Answer 7

network of reticular fibres + reticular cells
support and form stroma of organs
stroma of liver, spleen and lymph nodes

Question 8

Elastic CT
Features, function, location

Answer 8

parallel & free branching of collagen fibres
allow stretching
blood vessels, lung tissue, trachea

Question 9

Adipose CT
Function, location

Answer 9

thermal insulator, energy reserves, shock absorber
hypodermis, yellow bone marrow

Unilocular
- throughout the body except penis, scrotum, auricle of ears, eyelids

Multilocular
- rich in vascular & mito

Question 10

Cartilage
Features (4), functions (3), types

Answer 10

Avascular tissue with no lymphatic and nerve , does not repair when damage, dense CT, chondroblast - precursor , chondrocytes - in lacunae

development of bone, facilitate the movement of bone, bear mechanical stress

Hyaline, elastic, fibro

Question 11

Hyaline cartilage
type of collagen involved, features, functions, locations

Answer 11

type II
amorphous, growth in long bones
articulate the surface of synovial joint, structural support
articular cartilage, nose, resp. airway

Question 12

Elastic cartilage
type of collagen involved, features, locations

Answer 12

type II, elastic fibres, auricle of ears, auditory meatus, auditory canal, epiglottis

Question 13

Fibrocartilage
type of collagen involved, features, functions, locations

Answer 13

type I & II
herringbone pattern, disc between the joints
shock absorber, articulates the surface of clavicle & mandible
vertebrae, knee joint

Question 14

type of cells in CT

Answer 14

Fixed
- mesenchymal
- fibroblasts
- adipocytes

Wandering
- plasma cells
- mast cells

Question 15

Mesenchymal cells
functions, shape, e.g.

Answer 15

precursor
irregular, stellar or fusiform-shaped
osteoblasts, chondroblast, adipocytes, fibroblast

Question 16

Fibroblast cells
functions, shape

Answer 16

synthesis, secrete collagen fibres and elastin, maintain ECM
numerous, fusiform shaped

Question 17

Adipocytes
functions, shape

Answer 17

store fats, heat

unilocular (yellow)
- signet ring cells
- single fat droplet
- scant cytoplasm

multilocular (brown)
- many fats droplet & mitochondria

Question 18

Plasma cells
functions, shape

Answer 18

derived from B lymphocytes, synthesis antibiotics
ovoid, clock-face cells

Question 19

Mast Cells
functions

Answer 19

Cells filled with basophilic secretory granules
store chemical mediators ( histamines - itchiness, heparin - redness)
immediate hypersensitivity response

anaphylactic shock
allergic - degranulation of mast cells - release histamines, heparin - vasodilation - increase vascular permeability - smooth muscle contraction

Question 20

Types of fibres

Answer 20

collagen, reticular, elastic

Question 21

Collagen fibres
functions, features

Answer 21

serve as anchor
thick, tough, no branching, synth by osteoblasts, chrondoblast, odontoblast, fibroblast

procollagen - topocollagen - fibrils - fibres

Question 22

Ehler-Danlors Syndrome

Answer 22

due to collagen type III
-type IV - mutation of type III collagen
-type VI - abnormal lysyl hydroxylase
-type VII - deficiency of procollagen peptidase

Question 23

Osteogenesis Imperfecta

Answer 23

due to mutation collagen type I
bone malformation & fragility

Question 24

scurvy

Answer 24

deficiency of Vitamin C - less hydroxylation

Question 25

Reticular fibres
features, function

Answer 25

silver-staining, thin branching of collagen fibres type III

support network of organs

Question 26

Elastic fibres
features, function, location

Answer 26

extensive branching, flexible, elastic
deposition of elastin into fibrillin scaffold
artery wall, bronchi, bronchioles etc.

Question 27

Marfan’s Syndrome

Answer 27

mutation in fibrillin gene
eyes - dislocated lenses
bone - long arm, leg, fingers
heart - aortic aneurysm

Question 28

Ground substance
features, functions , types

Answer 28

hydrophilic, viscous complex of macromolecules, colourless

• allow passage of molecules & exchange of metabolites
• barrier for pathogens

Glycosaminoglycan (GAG)
proteoglycans
glycoprotein

Question 29

Glycosaminoglycan (GAG)
consists of ?

Answer 29

unbranched repeating disaccharides ( uronic acid + hexosamines)

bind to protein core - proteoglycan

Question 30

Proteoglycan
functions

Answer 30

structural components , anchor to matrix

Question 31

Glycoprotein
components
function

Answer 31

protein + branched carbohydrate
cell adhesions