👉 Thyroid is a gland in the endocrine system that produces hormones that regulate metabolism, growth, and development. It is located in the neck and consists of two main types of cells - the parathyroid gland (which is the largest) and the thyroid gland (which is smaller). The thyroid gland secretes three hormones: T3, T4, and TSH (thyroid-stimulating hormone, thyroxine, and triiodothyronine), which regulate metabolism, growth