In a well-balanced ecosystem, squirrels eat nuts, raccoons feed on squirrels, and bears feed on raccoons. it was observed that there were more squirrels and fewer raccoons. this situation indicates that . the least amount of energy from the sun will be received by the

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.

Identify any four organelles that should be present in the eukaryotic organism and describe the function of each organelle

Which organ controls breathing? lungs alveoli heart diaphragm