EVERYDAY SCIENCE

Detailed explanation-1: -Worms are invertebrate animals with bilateral symmetry. Worms have a definite anterior (head) end and a posterior (tail) end. The ventral surface of worms and other organisms is the bottom side of the body, often closest to the ground.

Detailed explanation-2: -Worms are members of several invertebrate phyla, including Platyhelminthes (flatworms), Annelida (segmented worms), Nemertea (ribbon worms), Nematoda (roundworms, pinworms, etc.), Sipuncula (peanutworms), Echiura (spoonworms), Acanthocephala (spiny-headed worms), Pogonophora (beardworms), and Chaetognatha (arrowworms).

Detailed explanation-3: -An invertebrate is an animal without a backbone. In fact, invertebrates don’t have any any bones at all! Invertebrates that you may be familiar with include spiders, worms, snails, lobsters, crabs and insects like butterflies.

Detailed explanation-4: -The kinds of aquatic invertebrates in freshwater systems include protozoans (single cell animals), freshwater sponges, various types of worms, mollusks (snails, clams, freshwater mussels), and arthropods (animals with jointed legs such as spiders, mites, crustaceans, and insects).