The pancreas responds by ____________ (B) and this causes target cells to ____________ (C).

To fill in the blanks appropriately, we need to understand the functions of the pancreas and its role in the endocrine system.

1. The pancreas produces hormones, most notably insulin and glucagon, which help regulate blood glucose levels.
2. When blood sugar levels rise after eating, the pancreas responds by secreting insulin (B).
3. Insulin facilitates the uptake of glucose by target cells, primarily in the liver, muscle, and fat tissue, leading to a decrease in blood sugar levels.
4. Therefore, the filling for the second blank would be that target cells take up glucose (C).

Thus, the complete statement could be: "The pancreas responds by secreting insulin (B) and this causes target cells to take up glucose (C)."

This illustrates the integral role of the pancreas in maintaining homeostasis in the body's glucose levels.