Because the three-horned alien is heterozygous, we know that three must be dominant to four, because the gene for the three horns is "hiding" the gene for four horns. Therefore, the three-horned alien has the genotype Tt (T for three horns, and t for four horns). The four horned alien must be tt, because that is the only way that a recessive trait may be seen. If you solve the punnet square on a cross between Tt and tt, you end up with half three (heterozygous) and half four (homozygous recessive) it is a bit easier to explain with something a little "closer to home" if you want me to explain it again, just say so, I don't mind!
The second pair of ribs or the true ribs
Answer:
Declining populations of phytoplankton, the basis of the marine food chain, will alter the seawater hues, potentially decimating fisheries. The world's oceans are warming and growing more acidic as a result of climate change, and a provocative new study suggests they'll be changing color too.
Explanation:
Hope this is good :)