Question 15

The parotid gland is an exocrine gland.

The parotid gland is classified as an exocrine gland because it secretes saliva through ducts into the oral cavity, thus fulfilling the definition of exocrine glands which release their products onto epithelial surfaces.

A) Parotid gland

The parotid gland is the largest of the salivary glands and functions as an exocrine gland by producing and releasing saliva through the parotid duct into the mouth. This direct secretion into a cavity distinguishes it from endocrine glands, which release hormones into the bloodstream.

B) Pituitary gland

The pituitary gland is an endocrine gland that secretes various hormones directly into the bloodstream, regulating numerous bodily functions. It does not have ducts for secretion, which is characteristic of exocrine glands.

C) Parathyroid gland

The parathyroid glands are also endocrine glands that release parathyroid hormone into the bloodstream to regulate calcium levels in the body. Like the pituitary gland, they do not secrete through ducts, thus disqualifying them as exocrine glands.

D) Pineal gland

The pineal gland is another example of an endocrine gland that secretes melatonin directly into the bloodstream to regulate sleep patterns. This gland does not function as an exocrine gland, as it does not have a duct system for secretion.

Conclusion

The parotid gland is definitively the correct answer as it is the only structure listed that functions as an exocrine gland, releasing its secretions through ducts. In contrast, the pituitary, parathyroid, and pineal glands are all endocrine glands that secrete hormones directly into the bloodstream without the use of ducts.