Some simpler animals lack what type of embryonic tissue?

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.

Arepair man charged $93.06 the price included 2 hours of labor and 40 service charge how much does the repairmen charge per hour for labor?

Food contains a sugar called ( ), which is broken down in a process called cellular ( ). this process uses ( ) to break down food molecules and provide energy for cells. fill in the parentheses