An error is that the scientist did not control their variables. They had one group of people playing the game at 6, and another group playing at 12. This means that other things might have affected the scores other than what was being tested, which was caffeine.
B - Many Agricultural practices bear some pretty bad impacts on the environment. A, C and D are incorrect.
Answer:
Four
Explanations:
See the attached diagrams.
Answer:
Mechanisms enabling one cell to influence the behavior of another almost certainly existed in the world of unicellular organisms long before multicellular organisms appeared on Earth. Evidence comes from studies of present-day unicellular eucaryotes such as yeasts. Although these cells normally lead independent lives, they can communicate and influence one another's behavior in preparation for sexual mating. In the budding yeast Saccharomyces cerevisiae, for example, when a haploid individual is ready to mate, it secretes a peptide mating factor that signals cells of the opposite mating type to stop proliferating and prepare to mate (Figure 15-2). The subsequent fusion of two haploid cells of opposite mating types produces a diploid cell, which can then undergo meiosis and sporulate, generating haploid cells with new assortments of genes.
Explanation:
Brainliest please?