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Annelida (Segmented Worms)

Introduction to this section:

Reading:
Invasive Earthworms Harm Forests Near the Great Lakes
Why Do Earthworms Surface After Rain?
Christmas tree worms have eyes that breathe, gills that see

Figure 1: Categories of Annelids

Video 1: Annelids: Powerful and Capable Worms (13:38)

Video 2: The Giant Earthworm (2:40)

Study Guide (Transcripts/Summaries):
Annelids are segmented worms that have a coelom, a complete digestive system, and a closed circulatory system. Segmentation means that similar units are repeated along the length of the body. In a closed circulatory system, a heart propels blood through a continuous system of vessels. Materials carried by the blood diffuse out of vessels and into cells, and vice versa. A closed circulatory system allows for faster distribution of materials throughout the body than does an open one. The categories of annelids are the ocean dwelling Polychaeta, the earthworms Oligochaeta, and the blood sucking leaches or Hirudinea.

Sources:
Figure 1: Categories of Annelids from: CK-12 Biology (say thanks), http://www.ck12.org/book/CK-12-Biology-Concepts/, Figure 11.26
Video 1: Annelids: Powerful and Capable Worms, https://www.youtube.com/watch?v=9Q9gh1k99rY
Video 2:The Giant Earthworm, https://www.youtube.com/watch?v=uO4lkv-jLRs