154 
Monitoring Stem Cell Research 
Type- 1 A diabetes: A form of insulin dependent diabetes, usually be- 
coming evident in childhood, resulting from an autoimmune reaction 
that destroys the pancreatic beta cells, so that the body cannot pro- 
duce its own insulin. In those cases where the condition is not ap- 
parent until adulthood, it is called latent autoimmune diabetes of 
adulthood. (LADA) 
Transcription factors: Specialized proteins that bind to specific sites 
on DNA and turn on or turn off the expression of different sets of 
genes. 
Trophoblast: The extraembryonic tissue responsible for implantation, 
developing into the placenta, and controlling the exchange of oxygen 
and metabolites between mother and embryo. (NIH) 
Twinning: Development of monozygotic twins, that is, when a very 
early embryo separates into two pieces, each of which continues de- 
velopment, so that two embryos actually come from one zygote. 
Uterine: Pertaining to the uterus. 
Virus: A submicroscopic pathogen composed essentially of a core of 
DNA or RNA enclosed by a protein coat, able to replicate only within 
a living cell. 
Xenotransplantion: A transplant of tissue from an animal of one spe- 
cies to an animal of another species. 
Zygote: The diploid cell that results from the fertilization of an egg 
cell by a sperm cell. (CR) 
PRE -PUBLICATION VERSION 
