When was mitochondria developed

Is a hamster and guinea pig part of the same species ?

Many farmers prefer cattle without horns because it is safer for their herds. the allele for no horns (n) is dominant to the allele for the presence of horns (n). a farmer mates a male with horns to a heterozygous female without horns. what is the chance that the offspring will have horns?

This part insulates the reaction chamber from the transfer of heat to or from the surrounding environment