Connective Tissues

Question 1

What is the definition of a connective tissue?

Answer 1

The connective tissue is defined as any supporting tissue that lies between other tissues and consists of cells embedded in a relatively large amount of extracellular matrix. Includes, bone cartilage and loose connective tissue.

Question 2

Where does the connective tissue come from?

Answer 2

• Mesodermal origin
• loosely packed
• unspecialized cells
• gelatinous ground substance
• from which connective tissue, bone cartilage and the circulatory and lymphatic systems develop.

Question 3

What is the connective tissue?

Answer 3

• Few cells within it, mainly fibroblasts
• Made up of an extracellular matrix
• Fibrous polymers mainly collagens
• Framework of vertebrate body
• Major component cartilage and bone
• Minor component brain and spinal cord

Question 4

What is a Fibroblast definition?

Answer 4

Fibroblast: A common cell type found in connective tissue. Fibroblasts secrete an extracellular matrix rich in collagen and other extracellular matrix macromolecules. Migrates and proliferates readily in wounded tissue and in tissue culture.

Question 5

What is the structure of Fibroblasts?

Answer 5

• Microtubules
• Filaments
• Junctions
• Heterogeneity
• Ageing
• Contraction and Motility

Question 6

What is Extracellular matrix definition?

Answer 6

The extracellular matrix can be defined as- a complex network of polysaccharides (such as glycosaminoglycans or cellulose) and proteins (such as collagen) secreted by cells. Serves as a structural element in the tissues and also influences their development and physiology.

Question 7

What is Extracellular Matrix function?

Answer 7

• Support for cells.
• Pattern of ECM regulates a) Polarity, b) Cell division, c) adhesion, d) motility.
• Development a) migration, b) differentiation.
• Growth Factors.

Question 8

What does Extracellular Matrix influence?

Answer 8

• Cell survival
• development
• migration
• proliferation
• shape and function

Question 9

What is Hyaluronan synthesis and function?

Answer 9

• Synthesised through the cell membrane.
• Has ability to bind lots of water molecules-useful for cosmetic industry
• Highly viscoelastic- treatment in osteoarthritis (stiff and painfull joints).
• Increased tumours and elevated at certain stages of wound healing.
• Linked increased fibroblast migration effect size dependent.

Question 10

What is collagen?

Answer 10

• Fibrous proteins
• Most abundant in mammals
• Primary feature long, stiff triple stranded helical structure
• At least 25 types of collagen
• 80-90% of all collagen Type I, II and III.
• Structural Unit is a triple helix

Question 11

What are the different types of collagen?

Answer 11

Question 12

What are diseases caused by an increase in Collagen?

Answer 12

• Scleroderma- rare chronic disease characterized by excessive deposits of collagen- growth factors
• Oral submucosa fibrosis: chronic debilitating and precancerous caused by chewing habit- increase in type III and then type I collagen

Question 13

What are diseases caused by Collagen insufficiency?

Answer 13

• Osteogenesis Imperfecta- brittle bones. 6 types-

Type 1- normal quality insufficient quantity A and B are when have dentinogenesis imperfecta (opalescent teeth).

• Collagenopathy, type II and XI.

Symptoms: poor bone development, problems with hearing, sight, cleft plate, small lower jaw.

Question 14

What are diseases caused by Collagen dietary problems??

Answer 14

Scurvy: a deficiency disease lack of vitamin C- needed for hydroxylation proline to hydroxyproline.

If not present- form too few hydrogen bonds in collagen.

Skin, bone teeth weakness and malformation.

Blood vessels weakened-bleeding