Chapter 51 - Salt and Water Balance and Nitrogen Excretion - 51.3 - Invertebrate Excretory Systems Use Filtration, Secretion, and Reabsorption - 51.3 Recap - Learning Outcomes - Page 1099: 1

Annelids such as earthworms have a fluid-filled coelom in each of their segments. The pressure from their closed circulatory system causes blood to be filtered across the thin, permeable capillary walls into the coelom. Waste products like ammonia diffuse from the tissues into the coelom to be expelled with urine.

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