Unsegmented Worms Flashcards
What phylum do flatworms belong to?
Platyhelminthes
What are the three classes of flatworms?
- Turbellaria
- Trematoda
- Cestoda
What are the characteristics of flatworms?
- Acoelomate
- Bilateral symmetry
- Show cephalization
- Respiration through skin
- Single opening to digestive tract (pharynx)
What is Class Turbellaria?
Planaria
What are characteristics of planarians?
Spade (shovel)-shaped head and two eyespots
- Eat protozoans for scavenge
- Are hermaphrodites
- Can reproduce by regeneration
- Are free-living (not sessile)
What do flame cells do?
They remove waste
What is Class Trematoda?
Parasitic flukes
What are characteristics of parasitic flukes?
- Have suckers on both ends of the body
- Can live inside or outside of host
- Nervous and excretory systems like turbellarians
- Hermaphrodites
- Have complex life cycles
What are the phases of a fluke life cycle?
- Egg
- Miracidium (free living in water)
- Sporocyst (in snail)
- Redia (in snail)
- Cercaria (free living in water/snail)
- Metacercaria (in 2nd intermediate host)
- Adult
What is Class Cestoda?
Tapeworms
What are characteristics of tapeworms?
- Parasitic
- Long, ribbon-like bodies
- Absorbs nutrients from host
- Hermaphrodites
What phylum do roundworms belong to?
Nematoda
What are characteristics of roundworms?
- Pseudocoelomate
- Slender bodies that taper on both ends
- Have mouth and anus
- Can be free living or parasitic
- Pinworms live in human intestines
- Trichinosis is a disease from eating infected pork
What are rotifers also known as?
Wheel animals
What are characteristics of rotifers?
- Transparent, free swimming, microscopic animal
- Freshwater and marine
- Have a ring of cilia around mouth that rotates like a wheel to bring in food
- Feed on unicellular algae, bacteria, and protozoa (protists)
- Have a muscular organ called the mastax behind the pharynx to chop food
- Nervous system composed of anterior ganglia and 2 long nerve cords
- Show cephalization (head end)
- Have 2 anterior, light sensitive eyespots
