Annelid worms are largely terrestrial and have segmented bodies, with the coelom partitioned via septa. Segmentation is an important evolutionary step towards specialization of body regions. The digestive tract, longitudinal blood vessels, and nerve cords run the length of the worm. However, each segment has its own set of excretory tubes, called metanephridia. Annelids have some cephalization, with a pair of cerebral ganglia at their anterior end. They also have a closed circulatory system, with muscular blood vessels to pump the blood through and around each segment. The well-developed coelom provides a hydrostatic skeleton. Below are examples of different types of Annelids.
Annelid worms are largely terrestrial and have segmented bodies, with the coelom partitioned via septa. Segmentation is an important evolutionary step towards specialization of body regions. The digestive tract, longitudinal blood vessels, and nerve cords run the length of the worm. However, each segment has its own set of excretory tubes, called metanephridia. Annelids have some cephalization, with a pair of cerebral ganglia at their anterior end. They also have a closed circulatory system, with muscular blood vessels to pump the blood through and around each segment. The well-developed coelom provides a hydrostatic skeleton. Below are examples of different types of Annelids.
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