Lesson 20 Terms Flashcards
Annelida
segmented worms
Aortic arches
function as tiny hearts that pump blood through the blood vessels
Clitellum
a barrel-shaped swelling around the body that assists in reproduction
Complete digestive system:
digestive system consisting of —–
digestive system consisting of a digestive tract and two body openings;
Worms use a shovel-like upper lip to scoop soil into their mouth and pass it into the pharynx.
It then moves to…
It then moves to the crop, and finally, the gizzard (stomach) where muscular contractions grind the soil
Cuticle function- roundworms
protects roundworms from the digestive enzymes of the host
Eyespots
sense light
Flatworms
Flatworms
1. Parasitic flatworms: organisms that live on or in another organism and benefit by taking nutrients from that organism at the expense of the host
Free-living Flatworms live —–
- Free-living flatworms: can live on land, in the ocean, or in fresh water
How many classes of flatworms?
- Three classes of flatworms:
a) Flukes (parasitic)
b) Tapeworms (parasitic)
c) Planarians (free-living)
Flukes
parasitic flatworms; require at least two hosts and spend part of their lives in snails
Ganglion
mass of nerve cells that functions like a simple “brain” in the anterior
Nematoda
roundworms
Nephridia
coiled tubes that are open at both ends and function as tiny kidneys
Nephridia
coiled tubes that are open at both ends and function as tiny kidneys
Parasites
organisms that live off of other organisms
Peristalsis
a wave-like process that moves food through the digestive system
Peristalsis
a wave-like process that moves food through the digestive system
Planarians
free-living flatworms
Planarians
free-living flatworms
Platyhelminthes
flatworms
Roundworms
- Bodies resemble a thread
- Live in nearly every environment
- Can be free-living or parasitic
Scolex
small, knoblike head of a tapeworm
Segmented worms
- Bodies appear to have ringed segments
- Found in different habitats
- Parasitic and free-living species
Setae
bristle-like structures that help segmented worms move
parasitic flatworm; have no mouth or digestive system, but absorb nutrients from their host
Tapeworms
