How is a clams respiration the same as an earthworm?

Both clams and earthworms respire through diffusion, allowing oxygen to pass directly into their bodies and carbon dioxide to exit. Clams use gills to extract oxygen from water, while earthworms rely on their moist skin for gas exchange. In both cases, a moist surface is essential for effective respiration. Additionally, both organisms have adaptations that maximize their surface area for gas exchange.