Answer and explanation;
The level of organization in human body is;
cells → tissues → organs → organ systems → the organism.
-Cells are the smallest unit of any living thing. it is the basic unit of living organisms.
-Tissues are groups of specialized cells working together to perform a specific function.
-An organ is a complex system of tissues working together to perform a life task for a human body. Examples: Heart, lungs, liver, kidneys, eyes, brain, stomach, intestines, and pancreas are a few of the organs that reside in the human body.
-An organ system is a group of organs working together to keep the human body alive. They include; Digestive system, Respiratory system, Endocrine system, Immune system, etc.