Exam 2 Study Guide

Question 1

What was the first transgene expressed in mice?

Answer 1

Somatotropin

Question 2

Provide three examples of practical transgenic animals

Answer 2

• chickens with greatly reduced capacity to spread H5N1 influenza
• cattle and goats have been genetically modified to express human lysozyme in their milk
• defensin A expression in mosquitoes to help kill malaria plasmodium after blood feeding

Question 3

Fragile X -

Answer 3

CGG repeats outside of gene coding region

- causes mental retardation

Question 4

Totipotent cells -

Answer 4

Able to produce any cell type found in the organism

Question 5

Stem cell niche -

Answer 5

• Local microenvironment that directly promotes or protects a population of stem cells
• two components: microenvironment and stem cell
• the environment emits cue or signals to the stem cells that keep the cell from differentiating

Question 6

Intrinsic vs. extrinsic

Answer 6

Intrinsic - belonging naturally; essential

Extrinsic - not part of the essential nature of something; coming or operating from outside

Question 7

Symmetrical vs. asymmetrical

Answer 7

asymmetrical - one daughter, one differentiated stem cell

Question 8

Signaling factors -

Answer 8

Induce stem cells to differentiate or keep them from differentiating

Question 9

HSCs

Answer 9

• found mostly in bone marrow

- two major: lymphoid and myeloid