connective tissue

Question 1

what are the functions of connective tissue?

Answer 1

-mechanical support
-protection and insulation
-compartmentalisation
-metabolic support

Question 2

what dopes the function of connective tissue depend on?

Answer 2

-matrix constituents
-proportions of matrix components
-organisation
-ability to interact

Question 3

what are the two types of connective tissue?

Answer 3

-areolar connective tissue
-fibrous/ dense connective tissue

Question 4

what does areolar connective tissue do? what does it consist of?

Answer 4

holds organs and epithelia in place and consists of a variety of loose proteinaceous fibres including collagen and elastin

Question 5

what does fibrous connective tissue consist of and what does it do?

Answer 5

consists of densely packed collagen fibres with great tensile strength and forms dermis ligaments and tendons

Question 6

whats the connective tissue in blood?

Answer 6

a fluid matrix around cells

Question 7

what’s the connective tissue in adipose?

Answer 7

mainly cells surrounded by thin matrices

Question 8

what is the connective tissue in bone?

Answer 8

its a rigid matrix of collagen fibres embedded in a mineralised matrix with hydroxyapatite

Question 9

what is the connective tissue in cartilage?

Answer 9

a matrix of polysaccharides with a few collagen II fibres

Question 10

what two types of cells do connective tissues contain?

Answer 10

either resident cells or transient cells

Question 11

what do fibroblasts do and give examples

Answer 11

responsible for secretion and maintenance of the matrix within connective cell tissue e.g.
-fibroblasts becoming myofibroblasts at the site of an open wound
-osteocytes to osteoclasts and osteoblasts in the bone
-chondrocytes to chondroblasts in the cartilage

Question 12

what are the components of extracellular matrix?

Answer 12

-collagen
-elastin
-proteoglycans
-glycoproteins

Question 13

what percentage of protein in the body is collagen?

Answer 13

25-30%

Question 14

what type of collagen does do basement membranes contain?

Answer 14

type IV and type VIIII

Question 15

what do basement membranes surround?

Answer 15

-muscle and fat cells
-underlie epithelial cells
-underlie endothelial cells

Question 16

what collagen are in facits?

Answer 16

type IX and type XII

Question 17

what are the different collagen orientations giving examples

Answer 17

-one direction in the force of extertion e.g. optic nerve
-basket like weave criss-crossed to withstand tension e.g. lamina cribrosa
-regular erray of small uniform diameter fibrils e.g. cornea

Question 18

how are the collagen fibrils in the cornea transparent?

Answer 18

by being within lamellae to allow light to be transmitted

Question 19

give two elastic fibres

Answer 19

elastin core
fibrillin microfibrils

Question 20

what is the role of elastic fibres?

Answer 20

-elasticity
-extensibility

Question 21

what are the roles of fibrilin in the lens?

Answer 21

to form suspensory fibres that make up the zonules that secure the lens

Question 22

how is both elastin and collagen useful in the tissue?

Answer 22

elastin allows deformation and recovery of the structure
collagen provides strength and limits deformation to prevent damage

Question 23

name a protein in the extracellular matrix. what does it contain? name some types of this chemical

Answer 23

proteogylcan which contains glycosaminoglycans (GAGs) some of which are chondroitin sulphate, heparan sulphate, dermatan sulphate and keratan sulphate

Question 24

what do proteoglycans have high sulphation?

Answer 24

so they have a negative charge. this makes them hydrophillic and allows them to form a hydrated gel which can withstand compression

Question 25

what are the three functions of proteoglycans?

Answer 25

-regulation of collagen fibril diameter,
-biomechanical function where they resist compression
-cell signalling

Question 26

give examples of glycoproteins

Answer 26

-fibronectin
-laminin
-vitronectin
-tenascin
-thrombospondin

Question 27

what are the functions of glycoproteins?

Answer 27

-cell-matrix attachment
-cell adhesion
-regulation of cell migration, cell attachment, matrix organisation, shape

Question 28

what is the function of glycosaminoglycans in connective tissue?

Answer 28

to give ability to resist compression