Why human beings are complex organism?

human beings are complex organism because

humans are made up of billion cells and a lot of system and organ.like blood circulatory system,digestion system and so all

Human beings are known to be complex organisms because they are made up of trillion of cell and organ systems that are dependent on each other. Some of the major systems are blood circulatory systems, the skeletal system, the digestive system, the nervous system and the respiratory system. Most of which are grouped into organ systems that have specialised functions.

The cells are organized from the simplest to the complex level in the body of the advanced organisms. These cells make up the tissues and then the organs. There is a division of labour among the cells which enhances efficiency and speed.

i think it is dna, i'm not totally sure but i think it might be.

where is the scientific experiment?