Multiple Choice A student looks at a slice of tissue on an unlabeled microscope slide. The student concludes the tissue is not from an animal because the cells in the tissue have A. membrane-bound organelles. B. nuclei. C. cell membranes. D. cell walls.

Which best explains why viruses do not have special structures or enzymes that allow them to make their own food? viruses can use energy in living cells that they infect. viruses can replicate inside a host that they infect. viruses can cause contagious illnesses in host cells. viruses integrate their rna or dna into infected cells.

Which factor affects the force of gravity between objects? check all that apply. direction distance mass shape time

What characteristic makes a cell membrane selectively permeable