"Human embryos" refers to the earliest stage of development of a human being, right after the fertilization of an egg by sperm. It is when the cells start multiplying and forming a tiny baby. Full definition
In this recent request, part of the plan is to avoid the ethical debate surrounding the use of human embryos in stem - cell research. (science.howstuffworks.com)
Researchers have used genome editing technology to reveal the role of a key gene in human embryos in the first few days of development. (cam.ac.uk)
Cells from human embryo injected into mouse brain can replace the mouse's own cells. (en.hdbuzz.net)