The Phoenix area of the Southwestern desert typically receives 8 inches of precipitation yearly, in two seasonal patterns. Even though it is an arid region, it has high biological diversity. Thin-leaf trees abound, such as palo verde and desert ironwoods wildlife includes insects, reptiles, many bird species, small rodents, and other mammals. Which factor in the Southwestern desert ecosystem is abiotic?

Which of the following is an advantage of using embryonic stem cells in medical research? a. the use of embryonic stem cells is much less expensive than the use of adult stem cells. o b. no living tissue is damaged when scientists use embryonic stem cells. o c. embryonic stem cells are able to differentiate into a wider range of cells than adult stem cells. d. there is no controversy surrounding the use of embryonic stem cells.