Final answer:
Excess food intake is promoted by low levels of leptin, which decrease the sensation of satiety, and high levels of ghrelin, which stimulate appetite. The correct answer is A. Low leptin, high ghrelin.
Step-by-step explanation:
Leptin and ghrelin are hormones that play crucial roles in regulating food intake and energy balance. Leptin is a hormone produced by adipose (fat) tissues and works to inhibit hunger, promoting a feeling of fullness or satiety. Thus, when leptin levels are low, there is less of a signal to the brain that the body has sufficient energy stores, leading to increased food intake. Ghrelin, on the other hand, is a hormone that stimulates appetite, signaling the body to increase food intake. High levels of ghrelin contribute to the feeling of hunger. Therefore, the condition that promotes excess food intake would be A. Low leptin, high ghrelin. This situation leads to a decreased sensation of fullness and an increased appetite, contributing to overeating.