Animals including humans have a complex system of living.
In the case of animals, they have the nervous system and endocrine system for control and coordination.
The Endocrine System is responsible for chemical coordination.
Numerous involuntary physiological activities are under the control of the endocrine system.
It consists of glands that release hormones.
Endocrine glands are also called ductless glands as they don't have ducts or tubes.
They release hormones into the blood.
Endocrine glands in animals are the hypothalamus, the pituitary gland, the pineal gland, the thyroid, the parathyroid, the thymus, the pancreas, the adrenal gland, and the gonads(testes in males and ovary in females).