Evidence indicates that plants increase the number of stomata in their leaves as atmospheric co2 levels decline. increasing the number of stomata per unit surface area should have the effect of doing which of the following?
1. increasing dehydration of leaf tissues2 decreasing dehydration of leaf tissues3. countering the effect of declining co2 on photosynthesis4.reinforcing the effect of declining co2 on photosynthesis

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.

Control of the body is accomplished by which of the following body systems? nervous system and circulatory system endocrine and repertory system circulatory and respiratory systems nervous system and endocrine systems

Which list is in order from simplest to most complex? a bacteria - virus - plant - protist b protist - bacteria - virus - plant c virus - bacteria - plant - protist d virus - bacteria - protist - plant