The third largest desert in the world, and the largest non-polar desert is the Sahara. Situated in North Africa, the Sahara makes up parts of Algeria, Chad, Egypt, Eritrea, Libya, Mali, Mauritania, Morocco, Niger, Sudan, Tunisia, and Western Sahara. The Sahara Desert spans over 9,400,000 square kilometers across the continent, and is the world's hottest desert.
âº A donor is also someone who gives blood or who agrees to give an organ or body part to help someone else. (Definition of âdonorâ from the Cambridge Academic Content Dictionary Â© Cambridge University Press)
Transplanta-. tion of tissues or cells from a donor who differs genetically from the graft recipient. induces an immune response in the recipient against alloantigens of the donor. graft. If not controlled, this response will destroy the graft. Recent discoveries have clarified how T lymphocytes, the principal agents of.