The first organisms on earth appeared approximately 3.5 billion years ago and were all unicellular. multicellular organisms have only existed for about one billion years. what evolutionary milestone made it possible for more complex, multicellular organisms to exist? appearance of heterotrophic cells appearance of autotrophic cells appearance of stem cells appearance of eukaryotic cells

Look at the photo of the leaf. which term best describes this leaf?

Humans are believed to have evolved in coastal regions in east africa. the region had an abundant supply of fish for early humanoids to eat. when scientists analyze the fads gene they see an interesting pattern. people whose families have lived in this area of east africa for generation show a high level of diversity in alleles for the fads gene. conversely, people whose families had migrated inland a moderate distance from sources of fish showed a much lower diversity for fads gene alleles. additionally, the fads alleles found in people whose family has lived inland for generation are almost all gene alleles which produce fads proteins with a high level of function and activity. how do anthropologists explain this?

Select the true statements about eubacteria. most live as decomposers and heterotrophs. most only thrive in a narrow range of environments. certain eubacteria are responsible for food poisoning. eubacteria thrive in extreme environments.