[Campbell Biology P.652] Which of the following statements about brown algae, as described i... | Practice Question

Which of the following statements about brown algae, as described in the provided text, is INCORRECT?

  • A2: The sea palm (Postelsia) uses a holdfast to maintain a firm foothold against crashing surf.
  • B2: Giant brown algae like kelps use gas-filled floats to keep their blades near the water surface for photosynthesis.
  • C2: Laminaria is a species of brown alga commonly used in soups and as a source of algin, a thickening agent.
  • D2: Brown algae evolved rigid stems similar to plants to provide support against gravity.

Explanation

The text explicitly states that brown algae adaptations are 'analogous, not homologous' to plants. It also mentions that while plants have rigid stems for support against gravity, brown algae use adaptations like gas-filled floats to keep their blades near the water surface, implying they do not rely on rigid stems for this purpose in the same way as plants. Therefore, the statement that brown algae evolved rigid stems similar to plants for gravity support is incorrect.