_____ is smallest gland in human body.

The correct answer is Pineal gland.

Key Points

• Pineal gland is the smallest gland in the human body with a length of about 5-8 mm.
• It is located in the epithalamus, near the center of the brain.
• The gland produces melatonin and serotonin and is, therefore, responsible for modulating sleep patterns.

Additional Information

• Largest gland of the human body - Liver
• The smallest exocrine gland - Goblet cell 
• The pancreas has both an endocrine and an exocrine function.
• Apocrine sweat glands are usually associated with hair follicles, continuously secrete a fatty sweat into the gland tubule.
• The parotid gland is a bilateral salivary gland located in the face.
• Ebner glands, also known as serous glands, are minor salivary glands located on both sides of your oral cavity toward the back of your tongue.