Final answer:
The primary difference is that exocrine glands use ducts to secrete their products, such as sweat or saliva, to the body's exterior, whereas endocrine glands release hormones directly into the bloodstream, influencing body functions without using ducts.
Step-by-step explanation:
The distinction lies in whether the gland uses a duct to secrete its products or directly releases them into the blood. Exocrine glands have ducts and their secretions are released to the body's exterior - for example, sweat, saliva, and digestive enzymes. An endocrine gland, on the other hand, does not have ducts and secretes its products, typically hormones, directly into the bloodstream.
Examples of exocrine secretions include mucous, sweat, and breast milk, all discharged through tubular ducts. Endocrine glands, such as the thyroid or adrenal glands, secrete hormones directly into the interstitial fluid and bloodstream, influencing various body functions.
Therefore, the main distinguishing feature between gland A and gland B could be the use of a duct in gland B, identifying it as an exocrine gland, whereas gland A, which secretes products directly into the blood, is an endocrine gland.
The distinction between the gland in A and the gland in B lies in their method of secretion. A) The gland in A utilizes epithelial cells to produce its products, while B) the gland in B uses a duct to release its secretions. C) The direct secretion of products into the blood is characteristic of endocrine glands, not relevant to this comparison. D) The method of secretion, specifically the use of epithelial cells versus a duct, is the key difference between the two glands.