The DNA sequences below show DNA segments for four different species. DNA SEQUENCES Species A TGG CAA CGG CAG ATT TAG Species B TGG CTA CGG CAG ATT TAG Species C TGC CTA CGG CTG ATT TAG Species D TGG CTA CTG CTG ATT TAG Scientists sometimes use DNA sequences such as these to determine the relatedness of different species. Which of the following is a necessary condition for scientists to use DNA sequences in this way?

What molecules will be best used to compare different species with the exact same sequence of amino acids? why would two species have the same protein even if the molecules in question is different? (hint: transcription to translation to protein).

Which statements best describe the differences or similarities between a comparative investigation and an experimental investigation? check all that apply. experimental investigations are best for showing cause-and-effect relationships, while comparative investigations do not necessarily show this type of relationship. comparative investigations are often impractical and unrealistic, while experimental investigations are the most practical and realistic kinds of investigations. comparative investigations allow for the use of a wide range of variables but do not have a control group, while experimental investigations involve variables that can be controlled. both experimental investigations and comparative investigations are designed to answer scientific questions. both experimental investigations and comparative investigations focus on making observations rather than collecting new data.

All ova contain sex chromosomes corresponding to: x y xx xy