[Campbell Biology P.740] Based on Figure 33.4 and its description, which statement accuratel... | Practice Question

Based on Figure 33.4 and its description, which statement accurately describes the body wall layers of a cnidarian?

  • A: The epidermis is derived from endoderm, and the gastrodermis from ectoderm.
  • B: The mesoglea is a cellular layer located between the epidermis and gastrodermis.
  • C: The gastrodermis is the inner layer, derived from endoderm, and where digestion is completed.
  • D: Digestion exclusively occurs in food vacuoles within the epidermis.

Explanation

Figure 33.4 and its description state that the gastrodermis is the inner layer, derived from endoderm, and that digestion is completed inside food vacuoles in the gastrodermal cells. The epidermis is the outer layer, derived from ectoderm, and the mesoglea is a gelatinous, not cellular, layer.