Final answer:
Humans have a longer digestive tract than frogs, which helps in the absorption of nutrients. Both have monogastric digestive systems with a single-chambered stomach, and neither species lacks a stomach.
Step-by-step explanation:
Differences Between Human and Frog Digestive Systems
The main difference between the digestive system of humans and frogs is that humans have a longer digestive tract than frogs. The increased length of the human digestive tract provides more surface area for the absorption of nutrients, particularly since humans may consume a varied diet that includes difficult-to-digest plant materials. In contrast, frogs have a shorter digestive tract as they generally consume more easily digestible food (insects and small invertebrates). Both humans and frogs have monogastric digestive systems with a single-chambered stomach, and neither lacks a stomach, which dismisses the suggestion that frogs lack a stomach.
Herbivores, like rabbits, have adaptations in their digestive systems such as an enlarged small intestine and cecum that provide additional surface area for nutrient absorption. These adaptations are due to the complexity of digesting plant materials like cellulose. Humans, while omnivores, also have a relatively long digestive tract compared to some other animals, which allows for a more efficient breakdown and absorption of the diverse array of foods they consume, including plant-based materials.