Healing and Repair (Ex2)

Question 1

Define Repair

Answer 1

the process by which lost or necrotic cells are replaced with vital cells

Question 2

What is Parenchymal Regeneration?

Answer 2

replacement of damaged tissue with cells of identical type

- sometimes leaving no trace of injury

Question 3

Parenchymal Regeneration can only occur if:

Answer 3

• the tissue has the capacity to regenerate

- the connective tissue framework of the tissue is maintained

Question 4

What is Fibrosis?

Answer 4

replacement by fibrous connective tissue or fibroplasia

- results in increased collagen within tissues

Question 5

What are Labile cells?

Answer 5

• continuously dividing cells
• proliferate throughout life, continuously replacing cell that have been destroyed
• regenerate after injury

Question 6

What are Stabile/Quiescent cells?

Answer 6

• demonstrate low normal level of replication
• can undergo rapid division in response to stimuli
• capable of reconstituting the tissue of origin

Question 7

What are Non-dividing/Permanent cells?

Answer 7

• have left the cell cycle, and cannot undergo mitotic division in postnatal life

Question 8

What are the four components of Fibrosis?

Answer 8

• migration and proliferation of fibroblasts
• deposition of ECM
• formation of new blood vessels
• maturation and organization of the scar

Question 9

What are the factors favoring fibrosis over regeneration?

Answer 9

• severe and prolonged tissue injury
• loss of tissue framework
• large amounts of exudate
• lack of renewable cell populations

Question 10

What are the consequences of fibrosis

Answer 10

• loss of functional parenchymal tissue
• alteration of physical properties of tissue
• skin with scar is more prone to tearing

Question 11

Describe Granulation tissue

Answer 11

• pink, soft, granular appearance on surface of wounds

- proliferation of new blood vessels and fibroblasts

Question 12

What are the four zones of Granulation tissue?

Answer 12

• zone of necrotic debris and fibrin
• zone of macrophages and in-growing capillaries
• zone of proliferating capillaries and fibroblasts
• zone of mature fibrous connective tissue

Question 13

Define Wound Healing

Answer 13

a process including connective tissue replacement and regeneration by which restoration of tissue continuity is achieved

Question 14

When does healing by first intention occur?

Answer 14

when there is little exudate and when tissue elements are closely approximated

Question 15

When does healing by second intent occur?

Answer 15

• when the edges of wounds are widely separated
• may contain a large amount of exudate and necrotic debris
• fibroplasia and scar formation will fill in defect