What is the part of the earth that you walk on called? mantle crust asthenosphere core

Four types of motile cells in human body?

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 are the doorways into and out of cells, attached to the membrane, and built in the rough er.