7. Regeneration 1

Question 1

Broad definition of repair in humans.

Answer 1

Combo of tissue regeneration and scar formation.

Question 2

3 systems that undergo regeneration in the human body.

Answer 2

1. Blood
2. Skin
3. GI tract

Question 3

Component of the body that provides the scaffolding for tissue repair during fibrosis.

Answer 3

Extra-cellular Matrix

Question 4

2 examples of physiologic proliferation of cells in the body.

Answer 4

1. Endometrial cell proliferation stimulated by estrogen in the menstrual cycle.
2. Thyroid gland growth under the influence of TSH

Question 5

2 examples of pathologic proliferation of cells in the body.

Answer 5

1. BPH

2. Thyroid Goiter

Question 6

Name the 3 groups of tissues in the body based on proliferative activity.

Answer 6

1. Labile Tissue - always dividing
2. Quiescent - divides with a signal
3. Non-dividing - arrested in G0 phase

Question 7

Since neurons are non-dividing cells, how does the body repair and replace the damaged neurons?

Answer 7

Replaces with glial (neuronal support) cells.

Question 8

Skeletal muscle cells that undergo slight differentiation and slight proliferative capacity.

Answer 8

Satellite Cells

Question 9

Name and describe the 2 pathways that stem cells use to maintain the cell numbers.

Answer 9

1. Obligatory Asymmetrical replication - one cell divides into 2 daughter cells. 1 Daughter cell differentiates while the other stays behind to divide again.
2. Stochastic Differentiation - one cell divides into either two differentiating cells or two more dividing cells.

Question 10

Term meaning that a cell can differentiate into any cell type in the body given the right stimulus.

Answer 10

Pluripotent

Question 11

Term meaning that 1 cell can divide and differentiate into a whole multicellular organism.

Answer 11

Totipotent

Question 12

Technique that can induce adult cells to become pluripotent.

Answer 12

Transfer a nucleus of a pluripotent cell into the cells of an adult so that damaged organs can be repopulated.

Question 13

Explain transdifferentiation VS Metaplasia

Answer 13

Metaplasia - stimulus affects already differentiated cells to induce stem cell differentiation into another phenotype.
Transdifferentiation - stimulus affects already differentiated cells and these cells change phenotype.

Question 14

3 sites where do hematopoietic stem cells come from?

Answer 14

1. Bone Marrow
2. Umbilical Cord
3. Peripheral blood of pts. receiving cytokines

Question 15

Multipotent cells that generate chondrocytes, osteoblasts, adipocytes, myoblasts, and endothelial cell precursors.

Answer 15

Marrow Stromal Cells

Question 16

Bipotential progenitor cells of the liver capable of dividing into hepatocytes or biliary cells.

Answer 16

Oval Cells

Question 17

Name 3 locations where stem cells reside in the skin.

Answer 17

1. Interfollicular areas (right by hair follicle)
2. Sebaceous glands
3. Buldge area of hair follicle

Question 18

Stem cells that maintain the cornea and reside at the junction of the cornea and the conjunctiva.

Answer 18

Limbal Stem cells

Question 19

Restriction point of the cell cycle that checks the cell’s DNA before DNA replication.

Answer 19

G1/S checkpoint

Question 20

3 proteins that regulate the G1/S checkpoint.

Answer 20

1. Cyclins
2. Cyclin-dependent Kinase (CDKs)
3. CDK-Inhibitors

Question 21

Checkpoint that monitors the DNA of cells after DNA replication.

Answer 21

G2/M checkpoint

Question 22

Growth factor that is mitogenic for hepatocytes, epithelial cells, and fibroblasts.

Answer 22

Epidermal Growth Factor (EGF)

Question 23

Growth factor that binds to the same receptor as EGF but is involved in malignant transformation of cells. Can be detected for cancer diagnosis.

Answer 23

Transforming Growth Factor-Alpha (TGF-A)

Question 24

Growth factor with mitogenic effects on hepatocytes and most epithelial cells.

Answer 24

Hepatocyte Growth Factor or Scatter Factor

Question 25

Growth factor that induces the migration and proliferation of fibroblasts, smooth muscle cells, and monocytes to areas of inflammation for tissue repair.

Answer 25

Platelet-Derived Growth Factor

Question 26

Growth Factor that promotes angiogenesis and vasculogenesis (in fetuses).

Answer 26

Vascular Endothelial Growth Factor (VEGF)

Question 27

Growth factor that contributes to hematopoiesis, angiogenesis, lung function, and formation of skeletal and cardiac muscles.

Answer 27

Fibroblast Growth Factor

Question 28

Growth factor that stimulates fibroblast chemotaxis, enhances collagen production, and inhibits collagen degredation. Also contributes to fibrosis in chronic inflammation.

Answer 28

Transforming Growth Factor-Beta (and also Related Growth Factor)

Question 29

2 cytokines involved in inflammation and wound healing.

Answer 29

1. TNF | 2. IL-1

Question 30

2 cytokines involved in inflammation and initiating liver regeneration.

Answer 30

1. TNF | 2. IL-6