What is the role of the greenhouse gases in the atmosphere?
a) they trap some of the sun’s heat energy within the atmosphere, to maintain earth’s average temperature.
b) they prevent most of the sun’s rays from reaching earth, thereby preventing earth from heating up.
c) they divert the sun’s heat from the equator to the poles, causing the ice caps to melt, leading to global warming.
d) they destroy the ozone layer, allowing harmful ultraviolet rays of the sun to reach the surface of earth.

Aresearcher designed an investigation to test what effect eating different types of food would have on blood insulin levels. she selected 10 male subjects who were all 25 years of age and in good health. the experiment took place over 3 days. at 8: 00 a. m. on each day, the subjects ate a meal consisting of only 1 type of food. they had their blood insulin levels measured after consuming the meal. on day 1 they ate a high fat diet, on day 2 they ate a high protein diet, and on day 3 they ate a high sugar diel what is the independent variable in this experiment? a the age of the subjects b the blood insulin level c the type of food consumed d the time of day the meal was consumed

18. which statement about cancer is true?

Explain the cellular functions that occur when antibiotics attack a bacteria cell. a. antibiotics target the cell wall, cell membrane, and the processes of protein and nucleic acids production in bacteria to rupture the cell. b. antibiotics create dormant resistant endospores to preserve the genetic material and rupture the cell. c. antibiotics target the cell wall and form a bridge-like connection to form conjugation. d. antibiotics use binary fission to grow twice its size, replications its dna, and split into two cells.