How long ago was it when the supercontinent existed?

Which class of organic compounds makes up the channels and pumps that move materials from one side of the cell membrane to the other? a.) carbohydrates b.) lipids c.) proteins d.) nucleic acids

1. which of the following is correct regarding opiates/opioids: a. they all have a natural component as a starting pointb. they have low addiction possibilitiesc. methadone binds to some of the same receptorsd. a and care correcte. all are correct

Which of the following is a testable hypotheses?