Which of the following are glands without ducts?
Endocrine glands
Exocrine gland
Heart
Glands without ducts are called "ductless" or "endocrine" glands. They release their secretions directly into the bloodstream. The pituitary is the master endocrine gland which regulates the secretions of other endocrine glands such as the pancreas, thyroid gland, gonads, adrenal glands, etc. The secretions of endocrine glands are called hormones.