ANSWER:
Thyroid and Parathyroid gland are related to the endocrine system. These are glands that secret different hormones in the body that regulate the several functions of the body.
Step-by-step explanation:
Endocrine system is a "network of glands" in the body. The endocrine glands secrete various hormones that regulate and control the body in different ways.
The hormones are released into the "bloodstream" by these glands. It is important for the endocrine system to be healthy and function in a proper manner else the body develops several problems.