What might happen if the human body did not have specialized cells, tissues, organs, and organ systems to maintain homeostasis?

The body wouldn't be able to fight off dangerous and deadly pathogens or produce energy from the nutrients a human digests. The body also wouldn't be able to undergo functions necessary for survival such as respiration, digestion, and excretion. Basically without a system of organs that assign each part of the body a specific job, the human body would just be a cluster of cells like most bacteria.