Do you think the allele for sickle cell anemia would be common in regions where malaria did not exist

The observations of hooke and van leeuwenhoek documenting the existence of microscopic cells formed the basis of what important theory? a. the cell theory stating that all living things are composed of cellsb. the theory of spontaneous generation, which held that life forms could arise spontaneouslyc. the theory of chemotherapy, or use of antimicrobials to destroy pathogenic organismsd. the germ theory of disease and causative agents

What is the cause hearing loss in human being

What are some of the immune functions of the lymphatic system? a. cleaning red blood cells from the blood and creating lymph fluids b.transporting lymph to the tissues and creating lymph fluids c.removing infectious agents and making white blood cells d.making red blood cells and removing infectious agents