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Flashcards in Connective Tissue Deck (166):
1

what provides the supportive and connective famework (or stroma( for all tissues of the body

connective tissue

2

What is connective tissue formed by?

cells and ECM

3

Is connective tissue vascular or avascular?

Connective tissue is directly supplied by blood and lymphatic vesselsI

4

What is ECM made out of ?

mixture of collagens, noncollagenous glycoproteins, and proteoglycans surrounding connective tissue

5

What is the role of connective tissue in the body?

Mechanical role: supporting and tissue repair Defensive role: inflammation (first reaction of defense) and immune responses Metaboliclly: Energy storage (adipose tissue) Template for bone formation: cartilage

6

What produces CT and ECM?

fibroblast

7

What is chondroblast?

a type of fibroblast that produces cartiledge

8

What are the three major groups of connective Tissue?

Embryonic Adult Special

9

Describe Embryonic CT

hydrophilic mainly ECM Whartons Jelly

10

Describe Adult CT

Loose Dense (regular and irregular) *structural diversity: the proportion of cells to fibers and ECM varies from tissue to tissue) therefore LooseCT and Dense CT

11

Describe Special Connective Tissue

Adipose Tissue Bone Tissue Cartiledge Hematopoeitic Tissue (bone marrow, reticular)

12

What are the major components of CT?

Fibers:Collagen, Elastic, Reticular Fibers Cells: resident (fibroblast), immagrant cells ECM ground substance):collagen, non-collagenous proteins and proteoglycans(trap water)

13

Fibroblast make

connective tissue fibers and ECM

14

Reticular CT

provide delicate meshwork to allow passage of cells and fluid

15

Elastic CT

provides elasticity (ligaments of vertebral column and wall of aorta)

16

How is CT classified?

1. proportion of cells, fibers, and ECM : dense or loose 2. Organization of fibers: regular or irregular

17

Embryonic CT

loose connective tissue covered by amnion the major component is hydrophilic ECM has alot of proteoglycans

18

What type of consistency does embryonic CT have?

jelly like...Whartons Jelly (mucoid CT)

19

Where is embryonic Connective Tissue Found?

Umbilical Cord Pulp of developing tooth

20

Loose CT

Has MORE CELLS than collagen fibers

21

What type of cells do fibroblast have ?

oval nucleur shape

22

Where is loose CT found?

mucosa and submucosa and surrounding blood vessels, nerves and muscles

23

Dense connective Tissues

MORE COLLAGEN FIBERS than cells dense regular Ct ( tendons, ligaments, cornea) dense irregular CT( reticular fibers and elastic fibers)

24

Metachromasia

change in color of staining shift in color of a dye from blue to purple DENSE CONNECTIVE

25

Types of Fibers and cells in Loose Connective Tissue

Fibers: abundant elastic fibers and collagen bundles embedded in ECM Cells: fibroblast-active cell (fibrocyte-not so active cell), mast cells, machrophages and blood capillaries

26

Where is Dense irregular CT found?

dermis (stratified squamous epithelium) submucosa of digestive tube more COLLAGEN FIBERS than cells

27

What are the cells present in Dense irregular CT?

Sparse fibroblast (separated by collagen bundles), mast cells, and marcphages

28

how to tell if dense irregular CT is making collagen?

if the nucleus is big cell is making collagen from the fibroblast when the nuclus is smaller then usual the cell is not making collagen (fibrocytes)

29

Describe dense regular connective tissue

regularly arranged collagen bundles compressed oval nucleus of the fibrocyte

30

What are the four major cell components of CT?

fibroblast (resident cells) macrophages mast cell plasma cell

31

What type of tissue is arygophilic

Reticular Tissue (can be identified ins torma of lymphatic nodule after being saturated with silver salts)

32

What type of tissue is RETICULAR CT?

adult dense irregular CT which reticular fibers predominate thing and branching strucutures

33

What is reticular tissue characteristic of?

lymphatic tissues

34

Reticular fibers are synthesized by?

fibroblast (reticular cells)

35

Reticular fibers form meshwork in which

lymphoid cells are embbeddded

36

Argrophilia

affinity for silver

37

Reticular tissue is what type of collagen?

type III

38

Reticular tissue is seen in....

lymphatic tissue and in bone marrow

39

Elastic Fibers are produced by

fibroblast and smooth muscle fibers

40

What type of CT is elastic?

adult dense irregular CT elastic fibers predominate and there is NO COLLAGEN!

41

Elastic tissue is characteristic of?

large blood vessels and ligaments

42

DEscribe the elastic fibers found in the wall of a blood vessel?

They are synthesized by smooth muscle cells and form discontinuous and concentric arrangements

43

What appear as wavy bands?

elastic tissue

44

Fibroblast synthesize and secrete

(ECM+COLLAGEN) BASIC SPECIFIC proteoglycans glycoproteins collagens (5 types) elastin fibronectin (glycoprotein) heparan sulfate proteoglycan

45

What do fibroblast synthesize that are part of the basement membrane?

fibronectin heparan sulfate

46

Collagen is a compondent of

collagen and the reticular fibers

47

What type of collagen is seen in the basal lamina?

type IV

48

What are the types of fibroblast?

reticular cells osteoblast (bone) chondroblast (cartilage) odontoblast (teeth)

49

Are reticular fibers PAS Positive?

reticular fibers and collagens in general are glycoproteins and therefore pas positive

50

Type I collagen

Fibrocartilage fibrillar Tendon, bone,dentin and dermis

51

Type II collagen

fibrillar ( thinner than type 1) Cartilage: hyaline and elastic

52

Type III

fibrillar lymphoid tissue Reticular collagen-> precollagen reticular lamina wound healing (replaced by type I) argyrophillic

53

Type IV

layers basal lamina binds to laminin does not form bundles

54

Type V

fibrillar amnion and chorion (in fetus) muscle and tendon sheaths doesnt form banded fibrils

55

Name the fibrillar collagen(s)?

Types: I, II, III, V

56

Name the non-fibrillar collagen(s)?

Type IV

57

Synthesis of Collagen Steps

In the RER 1. synthesis of precollagen and procollagen (triple helical arrangement of procollagen) 2. hydroxylation of lysine and proline by lysyl hydroxylase occurs in procollagen (requires vitamin c_scurvy) 3. glycosylation and disulfide bond formation Golgi apparatus 5packing and secretion of hydroxylated pro collagen Outside the cell 6.procollagen peptidase removes non helical end of procollagen and it becomes tropocollagen 7. Self-aggregation of tropocollagen molecule leads to formation of collagen fibrils (staggered array) 8. cross linking of collagen fibrils to form collagen fibers (FACIT COLLAGEN) 9. collagen bundle formation by proteoglycans and other glycoproteins

58

FACIT

fibril associated collagens with interrupted helices

59

lysl oxidase

cross links tropocollagen molecules stabilize staggered arangment of collagen fibrils to form fibers

60

Ethers Danlos Syndrome

hyperelasticty of skin and hypermobility of joints (dislocation) -defects in synthesis of procollagen collagen -type 1 collagen defect -mutations in procollagen peptidase or lysyl hydroxylase -cant form collagen fibers -defects in blood vessels and internal organs

61

procollagen peptidase

forms tropocollagen

62

lysyl hydroxylase

hydroxylation of lysine and proline needs vitamin c

63

Elastic Fibers is made in

RER and Golgi apparatus

64

Assembly of Elastin Fibers

RER 1. synthesis of 3 components of elastic fibers (fibulin 1, fibrillins 1 &2, tropoelastin) becomes proelastin Golgi proelastin is packaged and secreted into the extracellular space where it turns into tropoelastin ( with desmosine attached) Extracellular Space Assembly of fibulin 1, fibrillins and tropoelastin to produce elastic fibers

65

Elastic Fibers are made by

fibroblast and smooth muscle cells

66

Fibrillin 1

forcing bearing structural support

67

fibrillin 2

regulates the assembly of the elastic fiber

68

fibulin 1

required for co-assembly of fibrillins and elastin subunits

69

what type of fibroblast produce elastic fibers?

embryonic and juvenile fibroblast

70

Many tissues become ____elastic with age?

less elastic wrinkles

71

Marfans Syndrome

Issue with fibrillin 1 (chromosome 15) Increase in proteoglycans (they replace elastic lamallae) dilation of aorta mitral valve prolapse aortic dissection

72

Describe the periosteum in Marfans syndrome

abnormally elastic and does not provide oppositional force during development

73

Functions of Macrophage

1. turn over senescent (old) fibers and ECM material 2. present antigens to lymphocytes as part of inflammatory and immunologic responses ** ANTIGEN PRESENTING CELLS 3. Produces cytokines

74

where do macrophages derive from?

monocytes (cells formed in bone marrow)

75

what is a kupffer cell?

macrophage of the liver capture particles in liver blood cirulation

76

what is a osteoclast

macrophage of the bone dissolve bone during remodeling or when calcium in blood decreases

77

what is a microglial cell

macrophage of CNS removal of debris when there is destruction of cells in CNS

78

Where do monocytes ciruclate?

in the blood and migrate into the CT where they differentiate into macrophages

79

Macrophages have MHC

major histo compatibility complex 1. contain abundant lysosomes for breakdown of phagocytic materials have numerous phagocytic vesicles (phagosomes) for storage of ingest materials 3. nucleus has irregular outline

80

Macrophages as antigen presenting cells

put desktop picture on it

81

Mast Cells

source of vasoactive mediator (contained in cytoplasmic granules) metachromasia

82

What do the cytoplasmic granules of mast cells contain?

histamine heparin chemotatic mediators

83

What are vasoactive products of mast cells?

leukotrines

84

leukotrines

-are NOT present in granules -are leased from the cell membranes of mast cells -full of granules that form once the cell reaches the connective tissue

85

Name the types of Mast Cells

Mucosal MC Connective Tissue MC

86

Mucosal MC

predominantly in the intestines and lungs

87

Connective Tissue MC

granules more abundant in CT mast cells

88

what is a vasoactive mediator

mediates constriction and dilation of blood vessels

89

Origin of Mast Cells

bone marrow progenitor/precursor (lack cytoplasmic granules) when they migrate into the CT/lamina propria they proliferate and accumulate cytoplasmic granules

90

The migration of mast cells from bone marrow to tissue is regulated by

c-kit receptor (tyrosine kinase) and its ligand *(stem cell factor)

91

Clinical Significance of Mast Cells (antigen)

1. Antigen(allergen) binds to two adjacent IgE receptors and mast cell becomes IgE-sensitized 2. IgE-sensitized mast cell releases intracellular calcium 3. contents of cytoplasmic granules is rapidly discharged by degranulation 4. the degranulation will release histamine protease, and proteoglycans 5. synthesize inflammatory mediators derived from arachidonic acid (not present in granules ): cychoxygenase pathway-prostagladin d2 lipoxygenase-leukotrine c4

92

what occurs with excessive mast cell degranulation

allergic hypersensitivity reaction leads to shock (rapid drop inb lood, asthma hay fever eczema

93

Mast cell releases

-granule mediators (histamine, heparin, tryptase, chymase) -lipid mediators ( leukotrine) -cytokines (signaling molecules produced by specific cells of immune system)

94

Explain Asthma

release of histamine causes dyspnea (difficulty breathing) do to contraction of smooth muscle surrounding bronchioles and hyper-secretion of goblet cells and mucosal glands of bronchi

95

explain hay fever

histamine increases vascular permeability leading to edema (accumulation of fluid) -leukotrines induce increased vascular permeability associated with urticaria (swelling in dermis of skin) (vascular permeability is the permeability of blood vessels)

96

Plasma cells produce

all immunoglobins (single type per each plasma cell)

97

Plasma cells

well developed RER well developed golgi apparatus (gives light staining over nucleus & packages proteins) cartwheel nucleus (because of heterochromatin)

98

What are plasma cells derived from?

B lymphocytes (B cells)

99

Is the cytoplasm of plasma cells acidophilic or basophilic?

basophillic

100

The area around the nucleus of plasma cell becomes

slightly acidophilic

101

Cartwheel nucleus

plasma cell

102

How plasma cells are created

put desktop pic #2 1. antigen is taken up by a macrophage 2. the antigetn is stored in phagocytic vesicle which then fuses with a lysosome to become a phagosome 3. the phagosome has an acidic pH therefore it breaks up the antigen into small peptides 4. the small peptides attach to the MHC which is then exposed to TCELLS 5. the TCELLS then secrete cytokines or interleukins that bind to nearby B cells which are then induced into mitosis 6. the increased number of B cells now undergo differention into Ig secreting plasma cells

103

Adipose Cells

have MORE CELLS then collagen fibers and ground substance -most significant energy storage site in the bodyq

104

Cartilage and Bone

Both are dense CT with specialized cells

105

what type of ECM does cartilage have? Calcified or non calcified?

has non calcified ECM

106

what type of ECM does bone have? Calcified or non calcified?

calcified

107

What are the types of adipose cells?

Brown White

108

Brown adipose Cells

Multiocular store MANY lipid droplets and mitocondria thermogenic -dissipates energy instead of storing energy -heat generated by uncoupling production of ATP (UCP-1) -surrounded by alot of blood vessels

109

White adipose cells

Unicocular store SINGLE lipid inclusion provides a cushion and storage of energy (major reserve of long term energy)

110

Fat cells derive from

preadipocyte cells which derive from mesenchymal cell precursor

111

What is the effect of insulin on fat

insuling binding to insulin like growth factor 1 (IGF-1) causes preadipocytes to synthesize lipoprotein lipase (blood to fat cell transfer) this leads to primary fat cell formation in fetus

112

Obesity

disorder of energy balence accumulation of fat in liver insulin resistence dyslipidemia (alterations in blood fat levels) cardiovascular disease

113

Leptin

secreted by adipocytes regulates body weight

114

what occurs if one is leptin deficient

infertile and obese

115

leptin receptors share the same sequence as

cytokines receptors therefore it influences responses to infection and inflammatory responses

116

White fat nucleus

pushed to eccentric side position

117

_______fat lipids are in direct contact with cytosol

white

118

________fats do not contain a cytomembrane

white

119

Which has a more extensive blood supply? white or brown fat?

brown

120

What are the two requirements for thermogenisis?

1. mitochondrial biogenesis (production of new mitocondria) 2. uncoupling protein-1

121

Fat stains

xylene-dissolves fat/ only nucleus and plasma membrane left osimium tetroxide-stains fat brown (lipid rich myelin in nerves) SudanIII-alchoholic solution used for detection of fat in frozen sections

122

Where do chondroblast derive from?

mesenchymal cells

123

What are the three major types of cartilage?

hyaline elastic fibrocartilage

124

is cartilage vascular or avascular?

avascular nutrients are received by diffusion

125

Cartilage is made by?

chrondoblast/chrondcytes

126

Cartilage is surrounded by______

Perichondrium

127

Perichondrium

layer of undifferentiated cells that differentiate into chondroblast

128

chrondrocytes rarely

divide

129

Interstitial growth versus appositional growth

Interstitial growth-chondrocytes within the cartilage appositional growth-undifferentiated cells at the surface of the cartilage or perichondrium

130

Interstitial growth

mesenchymal cells turn into chondroblast 2. which form centers of chondrogenisis ( chondroblast surrounded by ECM) 3. the chondroblast divide by mitosis produce type II collagen, hyaluronic A, GAGS and form isogenous cell groups (daughter cells aka chondrocytes remaining in the same space lacunae) 4. isogenous cell group is surrounded by territorial matrix 5. wider interterritorial matrix surrounds the territorial matrix ACTIVE DURING ENDOCHONDRIAL OSSIFICATION

131

What do chondroblast deposit during mitosis?

type II collagen fibers hyaluronic acid GAGS

132

Appositional Growth

1. outermost cells of perichondrium (transitional zone between cartilage and surrounding CT) fibrous layer 2. inner cells of perichondrium (chondrogenic layer) differentiate into chondroblast and release type II collagen 3. new layer of carilage added and increases size of intial (anlagen/outline) 4. collagen grows

133

Chondroblast are a type of

fibroblast

134

Compomelic dysplasia

-mutation of sox 9 TF -encodes expression of type II collagen and proteoglycan ggrecan -with mutation null cells remain in perichondrium do not diff into chondrocytes

135

When chondroblast are trpped within spaces in the matrix called lacunae the cells are called

chondrocytes

136

What type of collagen does hyaline have?

type II

137

what type of collagen does elastic cartilage have?

type II

138

what type of collagen does fibrocartilage have?

type I

139

What type of cartilage has type II collagen?

hyaline and elastic

140

What are the special functions of hyaline cartilage?

shock absorber lubricated surface for joints

141

What type of cartilage lacks a perichondrium?

Fibrocartilage

142

where is hyaline cartilage found?

articular cartilage (area of body not lined by epithelium) temporary skeleton of fetus HIGH WATER CONTENT

143

where is elastic cartilage found?

external ear epiglottis auditory tube EVERY FLEXIBLE ECM CONTAINS ABUNDANT ELASTIC FIBERS

144

where is fibrocartilage found?

intervertebral disk, pubic symphysis articular disk of the knee ECM HAS LOW CONCENTRATION OF PROTEOGLYCANS AND WATER

145

how to distinguish between fibrocartilage and dense connective tissue?

pictures

146

Fibrocartilage is consisdered an intermediate between

hyaline cartilage and dense regular connectivetissue

147

Q image thumb

A image thumb
148

What type of adipose tissue is this?

What is the top line ?

What is the bottom line?

Q image thumb

brown adipose tissue

blood vessels

mutliocular adipocyte

149

What type of adipocyte is this?

What is the top line

what is the bottom line

Q image thumb

White 

eccentric nucleusuniolcular adipocyte

150

What type of CT is this?

Line 1 (top)

LIne 2

Q image thumb

embroyonic (whartons jelly)

nuclus of mesenchymal cell embedded in ECM

amnion

151

What type of CT is this?

Line 1 

Line 2

Line 3

 

Q image thumb

adult connective 

Loose (areolar)

Line 1-oval nuclus of fibroblast

elastic fibers (thin straight and branching

collagen bundles (thick and wavy)

152

What type of CT is this?

Line 1

LIne 2

LIne 3

Q image thumb

adult CT

dense irregular

oval nuclus of fibroblast

collagen bundles (thick wavy and irregularly arranged)

153

What type of CT is this?

Line 1 

LIne 2

LIne 3

Q image thumb

Adult CT

dense regular

1-skeletal muscle

2. regulary arranged collaen bundles

oval nucleus of birobcyte compressed by the regulary aligned collagen bundles

154

What type of CT is this?

Q image thumb

Reticular tissue

155

what type of Ct is this?

line 1

bottom line

Q image thumb

elastic tissue

elastic fibers

smoth muscle cells

156

What are these special types of CT?

Q image thumb

adipose

cartilage

bone 

hematopoeietic

(left to right)

157

Identify left to right

Q image thumb

macrophages 

fibroblast

collagen

158

What is this?

Q image thumb

mast cell

159

What are these?

Q image thumb

plasma cells

160

what type of carilage is this?

what is top line pointing to

Q image thumb

hyaline

chondrocyte

161

hyaline cartilage identify top to bottom

line 1

line 2

line 3

line 4

line 5

cline 6

line 7

Q image thumb

isogenous groups

nucleus

territorial matrix

lacunar rim

type Ii collagen

RER

interterriortiral matrix

162

What type of cartilage is this?

what is line 1

line 2

line 3

Q image thumb

elastic

perichondrium

chondrocytes

elastic fibers

163

What type of cartilage is this?

Q image thumb

Fibrocartilage

164

165

All cartilage is 

avscular

166