Connective tissues

Question 1

Macrophages have multiple functions. What are they?

Answer 1

• engulfment of invading microbes
• removal of damaged tissue, remodeling of repaired tissue
• remodeling of normal tissue during development, maintenance, and physiological restructuring.

Question 2

Fibrous ECM 3 types mentioned in lecture

Answer 2

Fibrillar (Type I)
Fibril-associated
Network forming (Type IV)

Question 3

Life cycle of fibrillar collagen:

Answer 3

mRNA made in nucleus —>ER for translation –>Golgi for processing [hydroxylation of proline, lysine] –>secreted into ECT–> cleavage of N and C terminal end to form N-telo peptide —> allows polymerization of collagen fibers

Question 4

N-telo peptides

Answer 4

Used as a marker for bone disease. Indication of excessive bone turnover.

Question 5

Ehlers-Danos syndrome

Answer 5

Defects in every step of collagen formation pathway. Has many clinical manifestations. Bruising, bone fracture, joint pain, bleeding, etc.

Question 6

Wound healing very basics

Answer 6

1) Inflammation: Mast cells secrete histamines and cytokines (interleukins), macrophages and lymphocytes also secrete these. These signals increase permeability of capillaries. Recruit white blood cells.
2) Proliferation: increase in fibroblast number and secretory capacity. Macrophages increase blood vessel formation
3) Remodeling: trying to recapitulate the damaged structure

Question 7

1. State the types, origins, and functions of the different cell types found within connective tissues.
2. Describe the components of the extracellular matrix, their functions, and how they are organized in different connective tissues.
3. For the proteins that form extracellular fibers, describe their types, their properties, and how they are made and assembled in the extracellular matrix.
4. Describe the basis and functional consequences of connective tissue diversity.
5. Describe how connective tissues are regulated upon tissue injury and the events that occur following wounding and inflammation.
6. Describe the structural relationship between connective tissue and epithelia, blood vessels, muscles and nerves.

Answer 7

xx