Which of the following is a mixed gland

Analyze the question: A mixed gland is one that works as both an exocrine gland (releases secretions through ducts) and an endocrine gland (releases hormones directly into the blood, with no duct).

Explain the concept:

• Exocrine glands have ducts, e.g. salivary glands and sweat glands.
• Endocrine glands are ductless and secrete hormones into the bloodstream, e.g. pituitary, thyroid and adrenal.
• Mixed (heterocrine) glands do both jobs.

Solution: Let's check each option.

• A. Pituitary: purely endocrine. It secretes growth hormone, ADH, and others straight into the blood.
• B. Adrenal: purely endocrine. It secretes adrenaline, cortisol, and aldosterone.
• C. Pancreas: mixed. • Exocrine part: it secretes pancreatic juice (amylase, trypsin, lipase) through the pancreatic duct into the duodenum. • Endocrine part: the islets of Langerhans secrete insulin and glucagon into the blood.
• D. Thyroid: purely endocrine. It secretes thyroxine.

Answer: The pancreas is the mixed gland, so the correct option is C.

Exam tip: Remember "Pancreas = Plays both roles". Whenever JAMB asks about a mixed gland, think of the pancreas first. The gonads (ovaries and testes) are also sometimes treated as mixed glands, but the pancreas is the classic example.