Scientists believe the first organism to appear on earth were prokaryotic which of the following best represents what the cell sturcture of these organisms may have looked liked is it a. contracile vacuole b. chlorplast c. dna or d. nucleus

In terms of alternation of generations, the internal parts of the pollen grains of seed-producing plants are most similar to a ) moss sporophyteb) moss gametophyte bearing both male and female gametangiac) fern sporophyted) fern gametophyte bearing only antheridia

Explain how sequences of amino acids in proteins can be used to reveal relationships among organisms.

In trying to determine whether dna or protein is the genetic material, hershey and chase made use of which of the following facts? a) dna contains sulfur, whereas protein does not. b) dna contains phosphorus, whereas protein does not. c) dna contains nitrogen, whereas protein does not. d) dna contains purines, whereas protein includes pyrimidines.