Class 11 NEET Biology Chemical Coordination and Integration

(b) : The thyroid gland is the only endocrine gland, that stores its secretory product in large quantity, normally about 10 days supplies in the extracellular space before discharging into the blood. It secretes iodinated hormone i.e., thyroxine and triiodothyronine that stored in the colloid which fills the follicle cells and released to blood when needed.