When is it summer in the Northern Hemisphere? when neither pole is receiving the most direct sunlight when the Northern Hemisphere is tilted toward the sun during an equinox when the Northern Hemisphere is closest to the sun

Which of the following is not a benefit of genetically modified foods? a.pest-resistant crops b.herbicide-resistant crops c.plants that do not require water?

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.

In order for you to hold your breath, your nervous system must send messages to your a. respiratory system b. digestive system c. heart in your cardiovascular system d. check in your muscular system