In: Anatomy and Physiology
summarizes you understanding of the organization of the body from the simplest elements to the More complex
Answer. The basic unit of the human body is the cell. It is the structural and functional unit of life. All the cells that are similar in function and structure forms the tissue. Tissue aggregate together to form the organ. Organs aggregate together to form the organ system and collection of organ system makes an organism like us.
Cell-tissue-organ-organ system-organism.
For example. The basic unit of kidney is nephron. These cells aggregate will form renal tissue because they will perform the function of purification of blood and moreover their structure would be similar.
This tissue will form the organs like kidneys ureters, urinary bladder and ureters. These organs collectively will form the excretory system in us.
Similarly, each organ system in our body like muscular system, nervous system, digestive system is made up of specific cells, tissues and organs and thus they form specific organ system. One organ system cannot be substituted by another.
Collection of all these organ systems will make us that's an organism.