Early land plant evolution occurred in moist lowland habitats; 400 million years ago they moved to the interiors of continents. Which of the following characteristics likely contributed to colonization of continental regions further from standing water? A. absorption of water through diffusion on photosynthetic tissue. B. ability to perform photosynthesis. C. development of vascular tissue for bulk flow. D. cell-cell adhesion which provide structural support for multicellularity.

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

How do accessory pigments chlorophyll?

'which of these statements about the scientific method is not true? all experiments must follow the same number of steps in the procedure. experiments may be repeated several times. some unexpected results can be beneficial. experimental results may or may not support the hypothesis.