Session 5-connective Tissue,cell roles,fibres,clinical diseases,cartilage, ossification and bone

Question 1

what are the 3 resident cell types that make up connective tissue?

Answer 1

fibroblasts
mesenchymal cells
macrophages (phagocytic and antigen presenting

Question 2

what is the role of fibroblasts?

Answer 2

maintain ECM, synthesise collagen, elastic and reticular fibres and ground substance
Important in wound healing-forms scar tissue

Question 3

what is the role of mesenchymal cells?

Answer 3

differentiate into other cells to maintain ECM

Question 4

Name 4 visitant (wanderer) cells found in connective tissue

Answer 4

• mast cells
• plasma cells
• fat/adipocytes
• leukocytes (wbc)

Question 5

what is the role of mast cells?

Answer 5

contain histamine (inflammatory response) and heparin (blood thinning)

Question 6

what is the role of plasma cells?

Answer 6

secrete antibodies….derived from lymphocytes ( remember: B cells and T cells)

Question 7

what are the 3 basic components that make up connnective tissue?

Answer 7

cells,extracellular fibres and ground substance (made up of GAGS..glycosoaminoglycans) good at absorbing water as GAGS are highly -ve, inflexible and hydrophilic

Question 8

name the 3 types of fibres found in connective tissue

Answer 8

collagen, reticular and elastic

Question 9

where is collagen synthesised?

Answer 9

RER

Question 10

what type of collagen are reticular fibres made up of?

Answer 10

type 3

Question 11

what makes elastic fibres so stretchy?

Answer 11

lysine

Question 12

name 2 places where areolar tissue is found (type of loose connective tissue)

Answer 12

• submucosa

- deep under skin

Question 13

what does areolar tissue contain?

Answer 13

fibroblasts, mast cells and macrophages (NOTE: most abundant fibre is collagen)

Question 14

name 2 places where dense, regular tissue is found

Answer 14

• ligaments

- tendons

Question 15

where is the main place where you are likely to find dense irregular tissue?

Answer 15

bone-periosteum, perichondrium,testes,dermis

Question 16

what is scurvy?

Answer 16

-vit C deficiency causing lower production of collagen and less connective tissue

Question 17

what causes Marfans syndrome, what inheritance is it and what are the symptoms?

Answer 17

defect in chromosomes coding for fibrillin (affects elastic fibres)
…large arteries rupture+smaller lumen
Autosomal dominant
Abnormally tall
Arachnodactyly (long spider like fingers)
Have frequent joint dislocation
At risk of catastrophic aortic rupture

Question 18

What is deficient in ethlers danlos disease?

Answer 18

type 3 collagen (reticular fibres)

Question 19

what does each chondrocyte in cartilage lie in?

Answer 19

lacuna

Question 20

what type of collagen is found in hyaline,elastic and fibro cartilage?

Answer 20

hyaline=type 2
elastic=type 2
fibro=type 1

Question 21

which type(s) of cartilage does the perichondrium surround?

Answer 21

hyaline and elastic

Question 22

which type of cartilage is the strongest and found in intervertebral discs?

Answer 22

fibrocartilage

Question 23

Hyaline and elastic cartilage are avascular-what does this mean?

Answer 23

rely upon diffusion to obtain nutrients

Question 24

what does red and yellow bone marrow contain or do?

Answer 24

red=RED blood cell synthesis

yellow=contain adipose tissue

Question 25

what happens when CA2+ is low in the blood?

Answer 25

PTH stimulates osteoclasts to Chew bone and break it down, decreasing bone mass

Question 26

what is the name of the process by which cartilage becomes bone?

Answer 26

endochondral ossification

Question 27

where does endochondral ossification begin and then continue?

Answer 27

begins in diaphysis (middle) of bone and then epiphysis (end)

Question 28

what is the name of the process by which loose connective tissue/mesenchyme becomes bone?

Answer 28

intramembranous ossification

Question 29

describe intramembranous ossification in terms of mesenchymal cells

Answer 29

mesenchymal cells differentiate onto osteoblasts which go on to produce osteocytes

Question 30

What is contained in granulation tissue(new connective tissue formed on a wound that requires healing)?

Answer 30

capillaries and fibroblasts

Question 31

name the 5 steps of bone remodelling

Answer 31

break–>haematoma and procallus of granulation tissue–>fibrocartilage callus–>ossification to form primary cancellous/spongey bone–>secondary compact bone

Question 32

Name the three parts of a small artery and state what is in them. From near to lumen to outside

Answer 32

Nearest to lumen:
Tunica intima-endothelial cells (simple squamous)
Tunica media-elastic lamellae (thin layer)
Tunica adventitia-collagen

Question 33

What gland has loose irregular and dense irregular tissue?

Answer 33

Mammary

Question 34

What is the difference between lipid droplet arrangement in brown adipose and normal adipose tissue?

Answer 34

Lipid droplets remain separate in brown adipose

Fuse in normal adipose to from single large droplet

Question 35

Name 11 places that contain hyaline cartilage.

Answer 35

Nose
Shoulder joint
Lungs,trachea,larynx
Rib cage
Elbow joint
Hands
Hip joint
Knee joint
Feet

Question 36

Name 3 places where fibrocartilage is found.

Answer 36

As discs between the vertebrae
Pubic symphysis (joins both halves of pelvis together)
Menisci

Question 37

What is the difference between appositional growth and interstitial growth and give an example of where this occurs.

Answer 37

Appositional-growth accomplished by the addition of new layers to those previously formed
Interstitial-growth from a number of different centres within an area
E.g. Fibroblast like cells in perichondrium give rise to chondroblasts which then develop into chondrocytes (appositional)
Chondrocytes deeper in cartilage form isogenous groups and then separate as they lay down matrix (interstitial)