Lecture 3 Connective

Question 1

Connective tissue 2 components

Answer 1

Extracellular matrix (ECM) and cells

Question 2

Extracellular matrix (ECM) 2 components

Answer 2

Ground substance, and Fibrous proteins (secreted by cells in ECM)

Question 3

What is ground substance made of?

Answer 3

water, polysaccharides (glycosaminoglycans), proteins

Question 4

What are glycosaminoglycans?

Answer 4

Long unbranched sugars made from repeating disaccharide units (e.g glucuronic acid, N acetylglucosamine)

Question 5

Proteoglycans

Answer 5

Core protein + glycosaminoglycan

Question 6

Sulphated GAGs

Answer 6

Dermatan, Keratan, Heparin, Chondroitin

Question 7

Non sulphated GAG

Answer 7

Hyaluronic Acid

Question 8

Applications of Hyaluronic Acid

Answer 8

Viscous, slippery binds cells together, lubricates joints, maintains eye-ball shape

Question 9

3 types of fibrous proteins

Answer 9

Collagen Fibres, Reticular (collagen type III) fibres, Elastic fibres

Question 10

Application of sulphated GAGs

Answer 10

Keratan: Strengthens bone, cartilage; lubricates cornea of eyes
Dermatan: Skin, Tendons, heart valves, blood vessels
Chondroitin: adhesive features in bone, cartilage, skin, blood vessels
Heparin

Question 11

Periorbital deposition and Thyroid disease

Answer 11

Over stimulation of thyroid gland (swells) –> over activation of fibroblasts –> increased secretion of fibrous proteins + increased GAGs and water –> orbital content increases causing enlargement of eye.

Question 12

Marfans Syndrome

Answer 12

Mutation of gene coding for Fibrillins on Chromosome 15 –> Transforming Growth Factor beta (TFGb) can’t bind properly to Fivrillin –> Fibrillin remains active so increased growth

Question 13

Marfans Syndrome symptoms

Answer 13

Tall, long limbs, collapsed or protruding sternum, weakened heart valves + blood vessels

Question 14

2 common CT tissue cell types

Answer 14

Fibroblasts; Adipocytes

Question 15

Other CT tissue cell types

Answer 15

Macrophage (wanderer), Plasma cell (antibodies), Mast cell (histamine), Leucocyte (white blood cell, phils and cytes)

Question 16

Plasma cells

Answer 16

Differentiated from B-lymphocytes, and produce antibodies. Found particularly in gut, spleen, lungs, salivary glands lymph nodes, RBM.

Question 17

Mast cells

Answer 17

Produce histamine which dilates blood vessels, obv found in blood vessels

Question 18

Macrophage

Answer 18

Differentiated from Monocytes. Wandering in CT at sites of III (infection, injury, inflammation) or fixed as specialised:
Dust cells in lungs, Kupffer cells in liver, Langerhan’s cells in skin

Question 19

Leucocytes

Answer 19

White blood cells including neutrophil, eosinophil, basophil, lymphocyte, monocyte

Question 20

Two classifications of CT

Answer 20

Embryonic, Mature

Question 21

Two types of embryonic CT

Answer 21

Mesenchyme (embryonic), Mucous

Question 22

Mesenchyme (embryonic)

Answer 22

Gives rise to all other CT, made up of mesenchymal cells in semi-fluid GS containing reticular fibres

Question 23

Mucous CT

Answer 23

Has scattered fibroblasts embedded in jelly-like GS, supports umbilical cord

Question 24

6 types of mature CT

Answer 24

Proper loose and dense; Fluid blood and lymph; Supporting bone and cartilage

Question 25

Loose CT

Answer 25

Fibres create loose framework; areolar, adipose, reticular. More cells than fibres.

Question 26

Dense CT

Answer 26

Fibres densely packed; regular, irregular, elastic. More fibres than cells.

Question 27

Blood and Lymph

Answer 27

Cardiovascular and lymphatic

Question 28

Supporting bone

Answer 28

Solid crystaline matrix

Question 29

Supporting cartilage

Answer 29

Solid rubbery matrix; Hyaline, Elastic, Fibrous

Question 30

Loose Reticular CT

Answer 30

Supporting structure of bone marrow, liver, lymphoid organs (lymph nodes, spleen, tonsils); predominantly consist of reticular fibres

Question 31

Loose adipose CT

Answer 31

Found in butt, front/sides of abdomen, orbit of eye. Stores energy as fat in white adipose, generates heat in brown adipose (insulation); predominantly adipocytes with central centre triglyceride droplet

Question 32

Loose Areolar CT

Answer 32

Widely distributed packing material found everywhere (general). Strength, support, elasticity from 3 fibres (collagen, reticular, elastic).

Question 33

Dense regular CT

Answer 33

Comprises tendons, ligaments, aponeuroses; stronger in 1D from parallel arrangement of predom collagen fibres. Slow healing due to less cells.

Question 34

Dense irregular CT

Answer 34

In dermis and forms protective (impact resistant) coating of eyeball and muscle fascia; weaker in 1D but stronger in all D from irregular arrangement of predom collagen fibres.

Question 35

Dense elastic CT

Answer 35

In blood vessels, respiratory passages, surrounds spine for strength and return to original shape; consists of elastic + collagen fibres

Question 36

Supporting Hyaline cartilage CT location

Answer 36

Found in respiratory cartilage (trachea, bronchi, nose), anterior ends of ribs and long bones, embryonic and fetal skeleton

Question 37

Supporting Elastic cartilage CT

Answer 37

Found in ears, tip of nose, larynx; consists of elastic fibres so very flexible to supporting bending

Question 38

Supporting Fibrocartilage CT

Answer 38

Found in intervertebral discs and joints for shock absorption, insertions of tendons and ligaments; very strong due to collagen fibres, protects blood vessels from compression.

Question 39

Osteoblasts to osteocytes

Answer 39

osteoblasts, lay down new bone by adding more collagen + mineralisation, difficulty receiving nutrients so turns into osteocytes

Question 40

Osteogenic to Osteoblasts

Answer 40

Osteogenic cells lay down collagen and become trapped in ECM, turns into --> osteoblasts

Question 41

Osteocytes

Answer 41

osteocytes, maintains tissue, exchanges nutrients and wastes, and have gap junctions

Question 42

4 types of bone tissue cells

Answer 42

Osteogenic cells, osteoblasts, osteocytes, osteoclasts

Question 43

Osteoclasts

Answer 43

Bone resorption (breakdown of matrix) and remodelling, formed from fusion of blood monocytes, large multi-nuclei cells,

Question 44

4 parts of osteon structure

Answer 44

Lamellae. Lacunae, Canaliculi, Central Haversion Canal

Question 45

Lamellae

Answer 45

Concentric rings hardened with mineral salts (calcium phosphate + calcium hydroxide= hydroxyapitite), and collagen (tensile strength)

Question 46

Lacunae

Answer 46

Small spaces between lamellae, contains mature osteocytes

Question 47

Canaliculi

Answer 47

Mini canals containing EC fluid for transport of oxygen, nutrients, waste to osteocytes in lacunae

Question 47

Central Haversian canal

Answer 47

nerves, blood and lymph

Question 47

Chondroblasts

Answer 47

Lay down hyaline cartilage callus

Question 48

Phagocytic cells

Answer 48

Monocytes which differentiate into macrophages; B-lymphocytes which differentiate into plasma cells; neutrophils

Question 49

Release substances to intensify inflammation

Answer 49

Basophil and Mast cells (immature are mobile, mature stay in tissues)

Question 50

Eosinophils

Answer 50

migrates to sites of parasitic infection and allergic responses

Question 51

Platelets

Answer 51

clotting (from megakaryocytes)