Sutherland found evidence for the presence of a G protein- coupled receptor for epinephrine in muscle cells. For this receptor to function normally, it must have at least how many binding sites, and what must be bound?

a. One: G protein
b. Two; epinephrine and G protein
c. Two: epinephrine and GTP
d. One: extracellular epinephrine
e. Three: epinephrine, G protein, and ATP

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.

this is a good question! i'll do some research and come back when i have the answer!