Many of the organ systems observed in vertebrates are present in the annelids,the simplest coelomates; an exception is the ________,which helps explain why earthworms leave the soil on rainy days.

Question

Quizplus · Accepted Answer

The missing organ system in annelids is the respiratory system, which is responsible for gas exchange with the environment. Earthworms breathe through their skin and require moisture to do so, which is why they come to the surface on rainy days.

Many of the Organ Systems Observed in Vertebrates Are Present