Tissue Repair And Healing

Question 1

Define healing process? [2]

Answer 1

-body replaces destroyed and dead tissue
-restoration of the architecture and function

Question 2

Explain the two types of healing processes?

Answer 2

1. Regeneration - There is a proliferation of cells to replace the damaged structures(complete reconstitution)
   - Stem cells need to be intact
2. Scar formation- healing by connective tissue deposition
   - depends on the extent (deep wound) of injury and tissue ability to regenerate

Slide 5

Question 3

What does cell regeneration involve? [1] And what is it dependent on? [2]

Answer 3

1. Involves cell proliferation
2. Dependent on the integrity of the extracellular matrix
   - development of mature cells from stem cells

Question 4

What causes healing by regeneration to not occur?

Answer 4

1. Severity of the injury
2. Chronic damage to the parenchyma and stromal framework

Question 5

What determines the number of cells and the size of the organ? Name three things? [3]

Answer 5

1. Proliferation activity of the cell
2. Stage of differentiation of the cells
3. Rate of Apoptosis

Question 6

Classify the body cells according to their proliferation activity?

Answer 6

1. Continously dividing cells (labile)
   - examples epithelium of skin, mucosa, BM? basement membrane
2. Quiescent cells(stable)- normally not dividing but if stimulated they can
   -examples: liver, kidney,pancreas, chondrocytes, osteocytes, mesenchymal cells - fibroblasts
3. Non dividing (permanent) cell- non proliferation in post natal life
   -examples: neurons, cardiac and skeletal muscle

Question 7

Name the two mechanisms of tissue regeneration and explain each?

Answer 7

Slide 9

Question 8

What are stem cells? Characteristics?

Answer 8

Slide 10

Question 9

Name the two types of stem cells?

Answer 9

1. Embryonic
2. Adult

Question 10

Name and explain 4 types of embryonic stem cells?

Answer 10

Slide 11

Question 11

Give facts about the Adult AKA somatic stem cells?
Where are the Adult stem cells found? [2]

Answer 11

Slide 13

Question 12

What is the difference between embryonic and adult stem cells?

Answer 12

Slide 14 table

Question 13

Describe the process of cell cycle?

Answer 13

Slide 15&16

Question 14

Define cell signaling

Answer 14

Slide 17

Question 15

Name and explain three modes of cell signaling

Answer 15

A-P-E
Slides 17 & 18

Question 16

Name and explain 4 phases of cell cycle?

Answer 16

Slide 20

Question 17

What are the functions of Extracellular Matrix? [6]

Answer 17

Slide 22
MMC
SSE

Question 18

Name three macromolecules groups found in ECM and their functions?

Answer 18

Slide 23

Question 19

Name two basic forms of ECM?

Answer 19

Slide 23

Question 20

Define Repair?

Answer 20

Slide 24

Question 21

Name five(5) basic components of repair by CT?

Answer 21

Slide 24

Question 22

Name and slightly explain steps in scar formation?

Answer 22

Slide 25

Question 23

What does healing by scar formation depends on?

Answer 23

1. Extent of the injury
2. Tissue ability to regenerate

Question 24

Control of normal cell proliferation is determined by three things, Name them? [3]

Answer 24

Slide 8

Question 25

Name two things in which stimulates cell cycle? [2]

Answer 25

Slide 15

Question 26

Define cell cycle checkpoints? [2]

Answer 26

Slide 21

Question 27

Cell can enter G1 either from? [2]

Answer 27

Slide 20

Question 28

Name all the checkpoints for the phases of cell cycle?

Answer 28

Slide 21

Question 29

Tissue repair and regeneration depends on? [3]

Answer 29

Slide 22

Question 30

What is the importance of Angiogenesis in both Physiological and Pathological processes?

Answer 30

Slide 26

Question 31

Angiogenesis in adult tissue can occur in two ways? [2]

Answer 31

Slide27 1. From preexisting blood vessels 2. From mobilization of EPSs (Endothelial Progenitor cells)

Question 32

Describe Angiogenesis from existing vessels?

Answer 32

Slide 29

Question 33

Describe granulation tissue seen macroscopic and microscopic? [2]

Answer 33

Slide 31

Question 34

Name three (3) things that lead to the formation of granular tissue?

Answer 34

1. Fibroblasts 2. Interspersed leukocytes 3. Vessels

Question 35

What stimulates the proliferation and migration of fibroblasts to injury site? [1] It is produced by? [1]

Answer 35

1. TGF-B 2. Macrophages

Question 36

Which ECM substances are produced by fibroblasts? [4]

Answer 36

Slide 33

Question 37

Give the 7 biosynthetic steps in collagen formation? [7]

Answer 37

Slide 34

Question 38

Describe the process of CT remodeling? [5]

Answer 38

Slide 35

Question 39

Describe the processes that occur as healing progress? [4]

Answer 39

Slide 36

Question 40

What are the three phases of Cutaneous wound healing? [3]

Answer 40

1. Inflammation- resulting from clot formation 2. Proliferation- granulation tissue formation, Proliferation of CT cells and re-epithelialization of wound surface 3. Maturation- ECM deposition, tissue remodeling and wound contraction Slide 37

Question 41

Name two types of cutaneous wound healing? [2]

Answer 41

Slide 38 1. Healing by first intention- clean cut 2. Healing by secondary intention- excisional wound or large defects

Question 42

Explain healing by primary/first intention? [4]

Answer 42

Slide 39

Question 43

Explain healing by secondary intention? [4]

Answer 43

Slide 40

Question 44

Explain fracture hearing? [3]

Answer 44

Slide 41

Question 45

What are the factors that affect healing? [2]

Answer 45

1. Local factors 2. Systemic factors

Question 46

Explain local factors in depth?

Answer 46

1. Infection- microorganisms in the wound can prolong inflammation 2. Size & location of the wound 3. Foreign materials- such as dirt, sutures 4. Pressure- blood supply may be disrupted leading to decreased blood flow to the surrounding tissue and delay healing 5. Trauma

Question 47

Explain systemic factors in depth? [5]

Answer 47

Slide 42 and Notes book 1.Vit C & protein- are necessary for adequate strength and synthesis of collagen 2. Glucocorticoid steroids (hormones)- is an anti inflammatory inhibiting arachidonic acid metabolism 3. Age- the elderly have slower healing processes, all phases of healing are affected even the collagen produced is off lesser strength

Question 48

What are the complications of healing? [7]

Answer 48

Slide 43- 49 and Notes book