Final answer:
The notion that insulin is the sole hormone to lower blood sugar is incorrect; while insulin is the primary hormone for this task, others contribute as well. Insulin also promotes fat synthesis and storage and has several other roles in energy storage and utilization, including affecting glycolysis and glycogen production in the liver.
Step-by-step explanation:
The statement that insulin is the only hormone that reduces blood glucose levels is false. Insulin is the main hormone that lowers blood glucose, but it is not the only one; other hormones like amylin, incretins, and perhaps others also contribute to the reduction of glucose levels, albeit not as profoundly as insulin does. Regarding the action of insulin on fat, it is true that insulin promotes the synthesis of fat and storage of fat in adipose tissue. Insulin facilitates the uptake of glucose into cells, including fat cells, and stimulates the conversion of excess glucose into triglycerides, which are then stored in adipose tissue. Insulin also has other significant roles, such as stimulating glycolysis, which is the metabolism of glucose for ATP generation. It encourages the liver to convert excess glucose into glycogen for storage and inhibits enzymes involved in glycogenolysis (the breakdown of glycogen) and gluconeogenesis (the production of glucose from non-carbohydrate sources). Furthermore, insulin promotes the synthesis of triglycerides and proteins, playing a crucial role in the body's energy storage and utilization.