By: Elizabeth Swinehart Pd.4
How to classify a worm?
All Worms Have...
-Cephalization (can respond to environment with sensory organs)
-No true limbs to move
What to know...
-also known as flatworms
-They have no true body cavity
-scavenger on the food chain
-They c0nsist of 3 germ layers
- Are classified into 3 classes (Cestoda, Turbellaria, Trematoda)
-Prefer dark environments
-Have no true skeleton
-No circulatory system
-Have suckers to attach to its host
-live in different body forms (egg, cyst, larvae, fluke)
-Cysts allow it to lay dormant until consumed and eggs hatch
Be aware of...
-they are also known as roundworms
-Have a hollow fluid filled cavity
-complete digestive tract
- use a cuticle which protects them form the inside digestive tract of their host
Soil Nematode (free living)
-Help with agriculture
-Do not possess a host
- Infect humans and mammals
-Live in the intestines
-Ingested by eating raw meat (unless frozen)
Knowing the basics...
- Their body is divided into segments
-Coelomate body plan
-evolved from primitive flatworms
Oligochaeta (free living)
-Also known as an earth worm
-Lives under the soil
-is nocturnal (active at night)
-circular muscles used to move the body
-commonly referred to as a leech
-Will attach to the outside of a hosts body using hooks/ suckers
-feeds off of blood/fluid