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Year 1 Cell Biology > Extracellular matrix > Flashcards

Flashcards in Extracellular matrix Deck (75):
1

What are the basic elements of the ECM?

1) Ground substance2) Fibers3) Granulation tissue

2

What are the characteristics of the ground substance?

1) Amorphous intercellular material 2) Hydrated 3) Fills space between cells and fibers4) Viscous5) Acts as lubricant, barrier, and provides structure6) Diffusion medium for metabolites, O2, CO2, growth factors

3

What are the molecular moieties of the ground substance?

1) Glycosaminoglycans2) Proteoglycans3) Multiadhesive glycoproteins4) Water

4

What are glycosaminoglycans comprised of?

Linear polymers of disaccharides

5

How is the hydrating effect of glycoasminoglycans accomplished?

Negative carboxyl groups attract cations, which attracts extracellular fluid

6

In Grave's disease, which extracellular matrix component is increased?

Glycosaminoglycans (e.g. hyaluronic acid, chondroitin sulfate)

7

What is another term for glycosaminoglycans?

Mucopolysaccharides

8

What are proteoglycans composed of?

Linear chains of glycosaminoglycans bound to a protein core

9

Linear chains of glycosaminoglycans bound to a protein core constitute what extracellular matrix component?

Proteoglycans

10

What is an aggrecan?

Proteoglycans non-covalently linked to hyaluronic acid

11

What is the term for proteoglycans non-covalently linked to hyaluronic acid?

Aggrecans

12

What is a syndecan?

Transmembrane proteoglycan

13

What type of proteoglycan serves as a co-receptor for fibroblast growth factor?

Syndecan

14

Syndecan serves as a co-receptor for what growth factor?

Fibroblast growth factor

15

What is the major proteoglycan found in the basement membrane and connective tissues?

Perlecan

16

What is the function of perlecan?

1) Cell adhesion2) Proliferation3) Differentiation4) Glomerular filtration5) Development6) Growth factor binding

17

How does gene inactivation for perlecan affect skeletal development?

Impairs skeletal development

18

What is the importance of versican?

Cell-to-cell and cell-to-ECM interactions

19

What are multiadhesive glycoproteins?

Glycoproteins that molecularly tether the cell to extracellular elements

20

Which glycoproteins molecularly tether the cell to extracellular elements?

Multiadhesive glycoproteins

21

What are the three binding sites for multiadhesive glycoproteins?

1) One for integrins2) One for collagen fibers3) One for proteoglycans

22

Where is fibronectin found?

1) Connective tissue2) Blood plasma3) Embryonic tissue

23

Where is laminin found?

Basal lamina

24

Where is nidogen (enactin) found?

Basal lamina

25

Where is tenascin found?

Embryonic tissue

26

Where is chondronectin found?

Cartilage

27

Where is osteonectin found?

Bone

28

Collagen is primarily made up of what amino acids?

1) Glycine2) Hydroxyproline3) Hydroxylysine

29

What is the most abundant collagen type?

Type I

30

What is the tissue distribution of type I collagen?

1) Dermis2) Tendon3) Bone4) Dentin5) Cementum6) Fibrocartilage7) Organ capsules

31

What is the function of type I collagen?

Resistance to tension

32

What is the tissue distribution of type II collagen?

Hyaline and elastic cartilage

33

What is the function of type II collagen?

Resistance to pressure

34

What is the tissue distribution of type III collagen?

1) Spleen2) Liver3) Lymph nodes4) Smooth muscle5) Skin6) Lungs

35

What is the function of type III collagen?

Maintains structure in expandable organs

36

What is the tissue distribution of type IV collagen?

Basal lamina

37

What is the function of type IV collagen?

Support of delicate structures and filtration

38

What is the tissue distribution of type V collagen?

Dermis

39

What is the function of type VII collagen?

Anchors the basal lamina to the lamina reticularis

40

Reticular fibers are composed of what type of collagen?

Type III

41

What stains could be used to detect reticular fibers?

1) Silver Methods2) PAS Reaction

42

What are the attributes of elastic fibers?

1) Slender and branched (loose CT)2) Densely arranged in bundles (ligamentum flavum)3) Detected by resorcin-fuschin or Verhoeff

43

What stains detect elastic fibers?

1) Resorcin-fuschin2) Verhoeff

44

How is nonfibrous elastic tissue arranged?

Fenestrated sheets or lamellae

45

Which cells synthesize elastic fibers?

1) Fibroblasts2) Smooth muscle cells3) Chondroblasts

46

Which three components must be synthesized to form elastic fibers?

1) Proelastin2) Microfibril-associated glycoprotein3) Fibrillin (1 and 2)

47

What is the defect associated with EDS IV?

Mutation in COL3A1 gene encoding type III collagen (reticular fibers)

48

What are the clinical consequences of EDS IV?

1) Varicose veins2) Aortic rupture3) Intestinal rupture

49

What is the defect associated with EDS VI?

Defective hydroxylation of lysine - destabilizes collagen strength

50

What are the clinical consequences of EDS VI?

1) Hyperelasticity of the skin2) Rupture of the eyeball

51

What is the defect associated with EDS VII?

Mutations of the COL1A1 and COL1A2 genes encoding type I collagen

52

What are the clinical consequences of EDS VII?

1) Joint dislocation2) Hypermobility of joints

53

What is the defect associated with scurvy?

Tropocollagen molecules cannot aggregate into fibrils due to decreased hydroxylation of proline caused by vitamin C deficiency

54

What are the clinical consequences of scurvy?

1) Gum ulceration2) Hemorrhages

55

What is the defect associated with osteogenesis imperfecta?

Mutations in the COL1A1 gene leading to reduction in type I collagen production

56

What are the clinical consequences of osteogenesis imeprfecta?

1) Spontaneous fractures2) Cardiac insufficiency

57

What is the defect associated with Strickler syndrome?

Mutation in COL2A1 gene encoding for type II collagen

58

What are the clinical consequences of Strickler syndrome?

1) Myopia2) Hypoplasia of mandible3) Arthritis

59

What is the defect associated with Marfan syndrome?

Mutation of fibrillin 1 gene on chromosome 15

60

What are the clinical consequences of Marfan syndrome?

1) Aortic aneurysm or rupture2) Myopia3) Detached lens4) Skeletal defects5) Pectus excavatum6) Scoliosis

61

What makes up the basal lamina?

Lamina lucida (variable) + lamina densa

62

What part of the basal lamina is secreted by epithelial, muscle, adipose, and Schwann cells?

Lamina densa

63

What makes up the basal membrane?

Basal lamina + lamina fibroreticularis

64

What part of the basal membrane is secreted by fibroblasts?

Lamina fibroreticularis

65

What makes up the lamina lucida?

1) Laminin2) Entactin (nidogen)3) Integrins4) Dystroglycans

66

What are the transmembrane receptors for laminin?

1) Integrins2) Dystroglycans

67

What is the lamina densa composed of?

1) Type IV collagen2) Fibronectin3) Perlecan

68

Type IV collagen, fibronectin, and perlecan make up what layer of the basal membrane?

Lamina densa

69

What is the lamina fibroreticularis composed of?

1) Fibronectin 2) Type I collagen3) Type III collagen

70

How is the basal lamina anchored to lamina fibroreticularis?

Anchoring fibrils of :1) Type VII collagen2) Fibrillin3) FIbronectin

71

The external lamina surrounds what elements?

Nonepithelial cells (muscle, adipocytes, Schwann cells)

72

Nonepithelial cells are surrounded by what type of basal lamina?

External lamina

73

What are the functions of the basement membrane?

1) Adhesion interface between epithelium and ECM2) Molecular filter3) Regulation of cell differentiation, proliferation, and organization4) Regeneration of cells

74

In Goodpasture syndrome, antibodies are formed against what type of collagen?

Type IV collagen

75

Antibodies against type IV collagen are formed in what disease?

Goodpasture syndrome