What kind of graph would most accurately depict changes in food consumption after CCK treatment in rats?

• A. A graph showing increased meal size
• B. A graph showing reduced meal size
• C. A graph showing no change in meal size
• D. A graph with fluctuating meal size

Answer: (B)

The choice indicating reduced meal size is correct because the hormone cholecystokinin (CCK) plays a significant role in regulating appetite and food intake. Upon treatment with CCK, studies have shown that it typically acts to suppress hunger and decrease meal size. CCK is released in response to food intake, especially fats and proteins, and it helps signal to the brain that the body is satiated.

By illustrating a graph that depicts reduced meal size after CCK administration, it accurately reflects the physiological response to this hormone. Research has consistent findings where increased levels of CCK correspond with smaller meals consumed, thereby confirming that CCK effectively reduces overall food intake at subsequent meals.

Understanding that CCK acts both in the gastrointestinal tract and the central nervous system to modulate hunger emphasizes the importance of representing its effects correctly on meal size in graphical form. The other options, while they highlight various theoretical responses to food consumption, do not align with the established physiological effects of CCK.