connective tissue

Question 1

what are the six types of connective tissue

Answer 1

• blood
• loose
• adipose
• cartilage
• bone
• dense

Question 2

define connective tissue

Answer 2

tissue that connects, supports, binds or separates other tissues or organs typically embedded with fibers/ collagen

Question 3

what are the three structural components of connective tissue

Answer 3

• cells
• fibres
• ground substance

Question 4

what are fibroblasts

Answer 4

produce fibers and extracellular matrix

important in wound healing

• large nuclei
• secrete collagen and elastin
• main connective tissue cells

Question 5

what are fibrocytes

Answer 5

• less active fibroblasts
• involved in tissue maintenance

Question 6

what are adipocytes

Answer 6

store energy in form of fat and provide insulation and cushioning

Question 7

what are mast cells

Answer 7

involved in immune responses especially allergic reactions by releasing histamine and other inflammatory mediators
located near blood vessels

Question 8

what are macrophages

Answer 8

immune cells responsible for phagocytosing pathogen, dead cells and debris

• fixed so permanently reside in a particular connective tissue/ organ
  in connective tissue called histocyte

Question 9

what is the difference in cells in white and brown adipose

Answer 9

white: unilocular
brown: multilocular

Question 10

what are unilocular adipocytes

Answer 10

single enormous lipid droplet

nucleus cytoplasm and organelles squeezed to periphery

function: padding, shock absorber, insulation and energy reserve

Question 11

what are multilocular

Answer 11

multiple small lipid droplets

nucleus, organelle, cytoplasm in centre

function: provides insulation and energy reserve

Question 12

what are the two types of fibers found in connective tissues

Answer 12

collagen
elastic

Question 13

describe type I collagen

Answer 13

fibrils aggregate into fibres and fibre bundles (skin, tendons)

Question 14

describe type II collagen

Answer 14

fibrils do not form fibres (present and elastic cartilage)

Question 15

describe type III collagen

Answer 15

fibrils form fibers around muscle, nerve cells and adipocytes and within lymphatic tissues and organs = RETCULIN

Question 16

describe type IV collagen

Answer 16

present in basement membrane

Question 17

what is the primary component of elastic fibres

Answer 17

elastin

Question 18

what do elastic fibres do

Answer 18

enfolds and is surrounded by microfibrils called fibrillin (a glycoprotein)

Question 19

where are elastic fibres found

Answer 19

dermis
artery walls
lungs
elastic cartilage

Question 20

what are reticular fibres

Answer 20

thin delicate fibres made of type III collagen

function: form mesh like network that provides structural support in soft tissues

location: liver, spleen, lymph nodes and bone marrow

Question 21

what is ground substance

Answer 21

key component in extracellular matrix
- amorphous gel like substance that fills space between cells and fibres
- provides a medium through which nutrients, gases, and waste products to diffuse between cells and blood vessels

Question 22

what are the components of ground substance

Answer 22

• glycosaminoglycans
• proteoglycans
• glycoproteins

Question 23

what are glycosaminoglycans

Answer 23

long unbranched polysaccharides that attract water to give ground substance its gel like consistency

Question 24

what are proteoglycans

Answer 24

proteins attached to GAG chains they help trap water contributing to viscosity

Question 25

what are glycoproteins in ground substance

Answer 25

adhesive molecules that help cells adhere to the ECM

Question 26

what are the functions of the ground substance

Answer 26

- hydration - support - nutrient diffusion - cell adhesion and migration - resistance and compression

Question 27

what are the two types of proper connective tissue

Answer 27

- loose - dense

Question 28

what are some example of loose connective tissue

Answer 28

areolar tissue, adipose, reticular tissue, mucoid

Question 29

what are some examples of dense connective tissue

Answer 29

regular and irregular

Question 30

give features of loose CT

Answer 30

- loosely arranged fibers, more ground sub - flexible and cushioning - more cells like fibroblasts - under skin, blood vessels and surround organs

Question 31

give features of dense CT

Answer 31

- densely packed fibers mostly collagen - provides strength and resistance to tension - fewer cells and less GS - found in tendons, ligaments and dermis

Question 32

where is mucoid CT found

Answer 32

umbilical cord virteous humor of eye

Question 33

what fibers are present in mucoid CT

Answer 33

type III collagen

Question 34

what cells are present in mucoid CT

Answer 34

immature fibroblasts

Question 35

describe the arrangement of fibers in regular dense

Answer 35

collagen fibers are aligned in parallel bundles

Question 36

what does the parallel arrangement of fibers in regular dense CT allow for

Answer 36

resist pulling forces in a single direction

Question 37

give an example of where regular dense CT is found

Answer 37

tendons and ligaments

Question 38

what types of collagen are found in tendons

Answer 38

type I and III

Question 39

what are collagen fibers packaged into in ligaments

Answer 39

fascicles separated by loose CT and ground sub

Question 40

give an example of where irregular dense CT is found

Answer 40

superficial layer of dermis

Question 41

why does the skin need irregular dense CT

Answer 41

to resist forces in multiple directions

Question 42

what do elastic fibers in skin allow for

Answer 42

degree of stretch and restoration to original shape

Question 43

what is fascia made up of

Answer 43

fibrous connective tissue containing closely packed bundles of collagen fibers oriented in wavy parallel pattern to direction of pull

Question 44

what is fascia able to resist

Answer 44

unidirectional tension forces until the wavy pattern fibers have been straightened out

Question 45

give three examples of clinical correlates of connective tissue disorders

Answer 45

- scurvy - Marfan's syndrome - osteogenesis imperfect-mutation

Question 46

how does scurvy affect connective tissue

Answer 46

Vit C deficiency - Vit C requires for intracellular production of pro-collagen which hydroxylates proline and lysine - without vit C body cannot form stable collagen leading to weakened CT and blood vessels and skin

Question 47

what are the symptoms of scurvy

Answer 47

- gum disease and tooth loss - bruising of skin and hair loss - bleeding - poor wound healing - weakness and fatigue - impaired bone development

Question 48

what is Marfan's syndrome

Answer 48

autosomal dominan disorder in which the expression of the fibrillin 1 gene is affected so elastic tissue is abnormal - sufferers are extremely tall and arachnodactyly, frequent joint dislocation, span greater than height

Question 49

how are the elastic fibers in Marfans defective

Answer 49

abnormally formed or reduced affecting tissues that rely on elasticity like aorta, ligaments and skin

Question 50

what is osteogenesis imperfecta

Answer 50

brittle bone disease due to mutated collagen fibers that do not knit together or not enough produced

Question 51

what is the origin oof osteogenesis imperfecta

Answer 51

different genetic aetiologies

Question 52

what are the symptoms of osteogenesis imperfecta

Answer 52

- weakened bones - short - blue sclera - hearing loss - hypermobility - poor teeth