Which of the following has both endocrine and exocrine functions?
A.
Thyroid gland.
B.
Pancreas.
C.
Anterior pituitary.
D.
Liver.
The Correct answer and Explanation is:
The correct answer is B. Pancreas.
Explanation:
The pancreas is a unique organ in the human body because it performs both endocrine and exocrine functions. Understanding the dual role of the pancreas provides insight into how the body regulates blood sugar levels and aids in digestion.
Endocrine Function: The endocrine function of the pancreas involves the secretion of hormones directly into the bloodstream. The pancreas contains clusters of cells known as the islets of Langerhans, which produce and release hormones such as insulin, glucagon, and somatostatin. These hormones play a critical role in regulating blood glucose levels:
- Insulin lowers blood glucose by facilitating the uptake of glucose into cells, especially muscle and fat cells, for energy production or storage as glycogen.
- Glucagon raises blood glucose levels by stimulating the liver to convert stored glycogen into glucose, which is then released into the bloodstream.
- Somatostatin regulates the secretion of both insulin and glucagon, ensuring that blood glucose levels remain balanced.
Exocrine Function: The exocrine function of the pancreas involves the secretion of digestive enzymes into the small intestine via the pancreatic duct. The pancreatic exocrine tissue consists of acinar cells that produce enzymes such as amylase, lipase, and proteases. These enzymes are crucial for breaking down carbohydrates, fats, and proteins in the food we eat:
- Amylase helps digest carbohydrates.
- Lipase aids in the digestion of fats.
- Proteases such as trypsin and chymotrypsin break down proteins into smaller peptides.
This dual function makes the pancreas a vital organ in both the endocrine and digestive systems. Disorders of the pancreas, such as diabetes mellitus (linked to its endocrine role) or pancreatitis (linked to its exocrine role), can have significant effects on overall health.
In contrast, the thyroid gland (A), anterior pituitary (C), and liver (D) do not have both endocrine and exocrine functions. The thyroid and anterior pituitary are purely endocrine glands, while the liver has multiple functions, but it is not classified as having an endocrine-exocrine dual role like the pancreas.