Oxygen constantly diffuses from air or water into an animal's bloodstream for this to happen the concentration of oxygen in the blood must be

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).

How does science influence the decisions made about social, economic, and political issues?

The earth's oceans are made up of chlorine, and trace elements. a) carbon, oxygen b) oxygen, silicon c) hydrogen, oxygen d) nitrogen, oxygen