Final answer:
Negative feedback loops are biological processes that maintain homeostasis by reversing deviations from a normal state. Examples include the regulation of blood sugar levels and body temperature. Blood clotting is a positive feedback mechanism, not negative feedback.
Step-by-step explanation:
Examples of negative feedback loops in biological systems include the regulation of blood sugar levels, heart rate, and body temperature, among others. An example of negative feedback is the lowering of blood glucose after a meal. In this process, when blood glucose levels rise, the pancreas releases insulin, which helps lower the glucose level back to normal.
If blood glucose levels are too low, the pancreas releases glucagon to increase the blood glucose levels. This regulation ensures that the blood glucose levels are kept within a normal range. Similarly, when body temperature increases above the normal range, processes like sweating are initiated to cool down the body, which is another example of negative feedback.