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Question 1

where is connective tissue found

Answer 1

between two other tissues

Question 2

What is CT made of

Answer 2

cells and ECM

Question 3

what are the 5 types of connective tissue

Answer 3

Loose connective tissue – lines serous membranes

Dense connective tissue-dermis of skin

Bone and cartilage

Adipose tissue (also example of loose CT)

Blood (also example of loose CT)

Question 4

what cells make up connective tissue and what is their main function

Answer 4

Fibroblast: found in skin dermis

Adipocytes-fat

Chondrocytes- in Cartilage

Osteocytes-in Bone

Haemopoietic (blood) cells

They all synthesise the ECM

Question 5

What is one important structure that determines tissue physical properties)

Answer 5

the ECM

eg bone - abundant calcified ECM because of bone function

Question 6

What are the two main classes of macromolecules in the ECM and what is their main function=

Answer 6

Polysaccharide chains (glycosaminoglycans, GAG)
usually linked to a protein hence making proteoglycans --> gel in which cells and fibrous proteins are embedded

Fibrous proteins (collagen, elastin and fibronectin)
important for structure, strength, flexibility, adhesion, cell positioning

Question 7

where do proteoglycans assemble

Answer 7

in the ER and Golgi

Question 8

GAG and proteoglycans can bind water to make gels. what is the main function of gels?

Answer 8

resist compressive force

permit rapid diffusion of nutrients, hormones, metabolites

Question 9

What is the structure of GAG

Answer 9

linear chain of 20-100s disaccharides (usually sulfated) such as heparin sulfate

Question 10

what’s a proteoglycan

Answer 10

one or more GAG attached to a core protein

e.g of proteoglycan is Biglycan: protein core+2 dermatan sulfate chains

Question 11

ECM is also made up of fibrous proteins: collage, fibronectin, and elastin. what’s the most common type of collagen and what is its main function

Answer 11

collagen type I

provides tensile strength

Question 12

mutation in collagen disease?

Answer 12

Ehlers-Danlos syndrome–> very elasticky skinm with very little structure integrity.

Question 13

ECM is also made up of fibrous proteins: collage, fibronectin, and elastin. what’s the main characteristics and functions of elastin?

Answer 13

polymer of tropoelastin associated with fibrillin (glycoprotein)
To form elastic fibres (elastic fibres most common in arteries)

Question 14

elastin is made of polymers of tropoelastin associated with fibrillin. what disease results from fibirilin gene mutaiton?

Answer 14

Marfin syndrom –> Ruptured arteries because of their rigidity.

Question 15

ECM is also made up of fibrous proteins: collage, fibronectin, and elastin. what’s the main characteristics and functions of fibronectin?

Answer 15

Fibronectin fibre in ECM; circulating soluble fibronectin in plasma, body fluids
Fibronectin fibres binds other cells through PM proteins (integrins) and ECM proteins (collagen)
Cell attachment to ECM and matrix organisation
Guiding cell migration
– development, wound healing
Fibronectin fibres secreted and assembled by cultured cells

Question 16

What are the three layers of the BM

Answer 16

Lamina densa (electron rich)
Lamina lucida (electron light) and reticular lamina under thatattaches to the underlying dermis.

Question 17

what’s the name of a cancer that has not broken through the BM

Answer 17

in situ carcinoma.

Question 18

What diseases do mutations in junctional proteins of the BL result in

Answer 18

Junctional EB

Question 19

What are the 5 types of epithelial junctions and their functions

Answer 19

Tight junctions (prevent passage of mucous across epithelium)

adherens. (tether adjacent cells together)

Desmosomal (Resist mechanical stress)

Gap (allow passage of small molecules between adjacent cells)

hemidesmosome (anchor epithelium to BM)

Question 20

What kind of junction links the epithelial cells to the BM

Answer 20

hemidesmosome

Question 21

What infectious. autoimmune and genetic disease is linked with deficiency is desmosomes

Answer 21

infectious: epidermal blisters
AI: pemphigus vulgaris
Genetic: desmoplakin Naxos disease

Question 22

what are the different types of cilia that exist

Answer 22

primary cilia: non motile- nearly on all cells for signalling pathway and chemosensoring

motile cilia: on trachea to move bacteria

Question 23

what is flagella made of

Answer 23

microtubule based skeleton

Question 24

Cells can put up protrusions to help them migrate. examples of those include

Answer 24

Pseudopodia
Large protrusion of the whole front of the plasma membrane
Amoeboid movement - cell crawling. How? By altering surface cytoplasm and plasma membrane
Cell put out protrusions of the plasma membrane through actin polymerisation. Neutrophils move that way.

Lamellipodia and Filopodia
much more finger like movment than pseudopodia
cell movement, contact, environmental sensing
• lamelliopdia – much finer, ruffles; epithelial cells, fibroblasts cell migration
• filopodia – spikes (finger like); migrating neural growth cones, fibroblasts allow cells to sense environment

Question 25

mirovili disease

Answer 25

infectious by enteropathogenic E coli –Z malabsorption and osmotic diarrhoea.