[Campbell Biology P.953] Based on Figure 41.6 and the accompanying text describing digestion... | Practice Question

Based on Figure 41.6 and the accompanying text describing digestion in a hydra, which of the following statements accurately describe its digestive process? Select all that apply

  • A: Hydras perform only extracellular digestion within their gastrovascular cavity.
  • B: Digestive enzymes are released from gland cells into the gastrovascular cavity to break down food into smaller particles.
  • C: The gastrovascular cavity serves both digestion and nutrient distribution functions.
  • D: Small food particles are engulfed by specialized cells of the gastrodermis for intracellular digestion in food vacuoles.
  • E: Digestion in hydra is exclusively intracellular, occurring entirely within food vacuoles.

Explanation

Figure 41.6 and its accompanying text describe a two-stage process for digestion in hydra. The text states: "Digestion begins in the gastrovascular cavity and is completed intracellularly after small food particles are engulfed by specialized cells of the gastrodermis." This contradicts options A and E, which claim digestion is solely extracellular or intracellular. Figure 41.6, step 1, shows "Digestive enzymes are released from a gland cell," and step 2 shows "Enzymes break food down into small particles," supporting option B. Figure 41.6, step 3, shows "Food particles are engulfed and digested in food vacuoles," supporting option D. Additionally, the text mentions that the gastrovascular cavity "functions in digestion as well as in the distribution of nutrients throughout the body," confirming option C.