Please refer to the Comptroller's publication Texas Property Tax Exemptions (PDF) for more information about these exemptions. Most of these exemptions have specific application forms that can be found through the exemption forms link in the box above.
The fetal DNA in a mother's blood can already reveal an infant's sex and other traits inherited from the father. But picking out a fetus's entire genome from its mother's is much tougher, says Dennis Lo, a chemical pathologist at the Chinese University of Hong Kong, who led the study.
The placenta is formed by cells that originate from the foetus and is therefore the first of the foetal organs to develop. What does the placenta do? The placenta contains a complex network of blood vessels that allow the exchange of nutrients and gases between the mother and the developing foetus. The blood supply of the mother does not actually mix with that of the foetus; this exchange occurs by diffusion of gases and transport of nutrients between the two blood supplies (see figure). The transfer of nutrients and oxygen from the mother to the foetus, and waste products and carbon dioxide back from the foetus to the mother, allows the growth and development of the foetus throughout pregnancy.