In fruit flies, the gene for red eyes (r) is dominant and the gene for sepia eyes (r) is recessive. if a red-eyed heterozygous fly (rr) mates with a sepia-eyed homozygous fly (rr), what are the possible genotypes of their offspring? (hint: you many want to complete a punnett square.)

rr only

rr, rr, and rr

rr and rr

rr and rr

If the gene for red eyes (R) is dominant and the gene for sepia eyes (r) is recessive.

The possible  of their offspring if Rr mates with rr is : 

The third option,  Rr and rr

hope this helps

Atp is is our little "pocket" of energy. of course, if you have too little, then it means you have too little energy, and you'll pass out. the way to not have enough, is to have no energy sources (glucose, fats, proteins). you can't have too many atp molecules. cycles like the krebs cycle produce it, but if you have too much of any substrate (or too little for that matter), the cycle stops and atp is no longer made (it stops until substrate levels are such that the process can go on). in any case, this is unlikely since atp is constantly hydrolyzed and remade, even while you're asleep. you won't have too much. if you have zero, you are dead or dying.