Which pairing correctly matches the group to a known excretory structure?

Which pairing correctly matches the group to a known excretory structure?

• A. Insects — Malpighian tubules
• B. Arachnids — Green glands
• C. Crustaceans — Nephridia
• D. Myriapods — Malpighian tubules

Answer: (A)

Malpighian tubules are the classic excretory structures of insects. These blind-ended tubes extend from the gut into the insect’s body cavity, actively taking up waste products and ions from the hemolymph and delivering them into the gut for elimination. This arrangement lets insects conserve water by producing concentrated waste, often as uric acid, which is efficient for terrestrial life. Green glands, or antennal glands, are characteristic of crustaceans, not arachnids, so pairing crustaceans with green glands isn’t accurate. Nephridia are typical of annelids (like earthworms), not crustaceans. Myriapods have a different excretory arrangement and are not classically described as using Malpighian tubules. Therefore, the most accurate match is insects with Malpighian tubules.

Malpighian tubules are the classic excretory structures of insects. These blind-ended tubes extend from the gut into the insect’s body cavity, actively taking up waste products and ions from the hemolymph and delivering them into the gut for elimination. This arrangement lets insects conserve water by producing concentrated waste, often as uric acid, which is efficient for terrestrial life. Green glands, or antennal glands, are characteristic of crustaceans, not arachnids, so pairing crustaceans with green glands isn’t accurate. Nephridia are typical of annelids (like earthworms), not crustaceans. Myriapods have a different excretory arrangement and are not classically described as using Malpighian tubules. Therefore, the most accurate match is insects with Malpighian tubules.