Lesson 11 ·Class 9 · Five Kingdom Classification · Sort Lab
Comparing the Worm Phyla
Flat, round, and segmented.
Three phyla are all called worms. Sort each feature or example correctly.
Sorted 0/9
All items sorted — check each bin.
Free play — sort every item into the bin it belongs in; each correct drop tells you why. Switch to when you're ready to test yourself.
Follow the body cavity: none in flatworms, false in roundworms, true in annelids. That is the real evolutionary story here.
What this lesson covers
Challenges to clear
- Fill the Annelida bin correctly.
- Sort every item.
- Fill the Platyhelminthes box — the flatworms with no body cavity at all.
The task
Three phyla are all called worms. Sort each feature or example correctly.
What this lesson covers
- Platyhelminthes — Flatworms: Body flattened dorsoventrally, like a ribbon (Flatness keeps every cell close to the surface — they have no circulatory system.); Tapeworm and liver fluke (Mostly parasitic, with hooks and suckers for attachment.); Has no body cavity at all (Acoelomate — the space between gut and body wall is packed with tissue.)
- Nematoda — Roundworms: Body cylindrical and pointed at both ends (Unsegmented, with a tough cuticle.); Ascaris, hookworm and filarial worm (Many are serious human parasites.); Has a false body cavity, not lined by mesoderm (Pseudocoelomate — a genuine cavity, but not a true coelom.)
- Annelida — Segmented worms: Body divided into true ring-like segments (Metameric segmentation, inside and out.); Earthworm and leech (Mostly free-living, and useful to the soil.); Has a true coelom lined by mesoderm (The first phylum with a real body cavity — it allows organs to develop properly.)
Hint
Follow the body cavity: none in flatworms, false in roundworms, true in annelids. That is the real evolutionary story here.