Question

which shows three human body parts in order from the simplest level of organization to the most complex? red blood cell → nervous system → bone tissue nervous system → bone tissue → red blood cell red blood cell → heart tissue → circulatory system bone tissue → red blood cell → nervous system

Explanation:

The levels of organization in the human body from simplest to most complex are: cell → tissue → organ → organ system. A red blood cell is a cell. Heart tissue is a tissue. The circulatory system is an organ system.

Answer:

red blood cell → heart tissue → circulatory system