Single-celled organisms such as bacteria perform every function needed for life in their one cell. Bacteria have no tissues, organs, or systems. Why do animals such as humans need levels of organization?

Levels of organisms are organised to keep up the homeostasis of the living organism which is very important for the animals.

Explanation:

Higher levels of association are worked from lower levels. In this manner, particles join to shape cells, cells consolidate to frame tissues, tissues join to shape organs, organs join to shape organ frameworks, and organ frameworks consolidate to frame life forms.

Cells are sorted out into tissues, and tissues structure organs. Organs are sorted out into organ frameworks, for example, the skeletal and strong frameworks. The entirety of the organ frameworks of the body cooperate to keep up homeostasis of the living being. In the event that homeostasis comes up short, passing or infection may result.

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