[Campbell Biology P.991] Which of the following statements accurately describes a key differ... | Practice Question

Which of the following statements accurately describes a key difference between tracheal systems and lungs as respiratory organs?

  • A: Tracheal systems directly deliver oxygen to body cells, while lungs rely on a circulatory system for gas transport to cells.
  • B: Lungs are found only in vertebrates, whereas tracheal systems are present in both vertebrates and invertebrates.
  • C: Gas exchange in tracheal systems primarily occurs across the skin, while in lungs it occurs through specialized internal surfaces.
  • D: Tracheal systems are typically subdivided into numerous pockets, while lungs are simple, unbranched structures.

Explanation

The text states that tracheal systems 'bring air within a very short distance of virtually every body cell in an insect,' implying direct delivery and that 'efficient exchange of O2 and CO2 does not require the participation of the animal's open circulatory system.' In contrast, for lungs, it notes that 'the gap must be bridged by the circulatory system, which transports gases between the lungs and the rest of the body.' This highlights the key difference in gas transport mechanisms.