Chapter 14: Flatworms, Mesozoans, Ribbon Worms

Are flatworms, mesozoans, and ribbon worms diploblastic or triploblastic?

triploblastic

Symmetry of flatworms, mesozoans, and ribbon worms?

bilaterally

Protostomia

blastophore forms mouth

Blastophore forms anus

deuterostomia

What type of body cavity is present in flatworms, mesozoans, and ribbon worms?

all

Phylum Acoelomorphoa include

small flat worms

Phylum Acoelomorphoa live in

marine sediments

In Phylum Acoelomorpha, rootlets of epidermal cilia form

interconnecting networks

Are Phylum Acoelomorpha free-living, commensal, or parasitic?

all

The gut in Phylum Acoelomorphoa is

absent and saclike

Mesodermal muscle cells in Phylum Acoelomorpha are

longitudinal, circular, diagonal

How are the nerve cords arranged in Phylum Acoelomorpha?

radially

Phylum Acoelomorpha reproduces asexually and sexually by

budding and internal fertilization

What systems do Phylum Acoelomorpha lack?

excretory and respiratory

Phylum Platyhelminthes include

real flatworms

Phylum Platyhelminthes roots

platys (flat) and helminths (worm)

What phylum is free-living or parasitic?

Platyhelminthes

What has cellular, cilaited epidermis?

Turbellarians

What is rod shaped and filled with water for protection in Turbellarians?

rhabdites

Turbellarians have ____ gland adhesive organs

dual

What do parasitic flatworms use as a covering

syncytial tegument

Turbellarians and parasitic flatworms both have

multiple types of muscle fibers under epidermis

Digestion is extracellular or intracellular in Phylum Platyhelminthes?

both

Digestion parts in Phylum Platyhelminthes include

mouth, pharynx, intestine

Do most parasitic forms have a digestive system?

no

Protonephridia

waste excretion and osmoregulation organ

Nerve types

sensory, motor, association

Ocelli

photosensitive eyespots

Statocysts

equilibrium

Rheoreceptors

sense water currents

Asexual reproduction by

fission and fragmentation

Sexual reproduction by

monoecious but cross fertilizing
free swimming larvae

Class Turbellaria include

free living worms

Class Trematoda include

parasitic flukes

Where does Class Trematoda inhabit in?

organ systems

Clonorchis

human liver fluke

Miracidium

free swimming larvae

Sporocyst

penetrates tissues of a mollusc and encysts

Schistosoma

blood fluke

Swimmer’s Itch normal hosts are

birds

Paragonimus

lung fluke

How can you get lung flukes?

undercooked crab

Class Monogenea are

parasites on fish gills

Class Cestoda include

tapeworms

Does Class Cestoda have a digestive system?

no

The entire body is covered in ____ in class Cestoda

microtriches

Planuloid ancestor hypothesis

one branch = radially/biradially symmetrical = cnidaria
other branch = bilaterally symmetrical = platyheminthes

Phylum Mesozoa roots

mesos (middle) and zoon (animal)

What is the missing link between protozoa and metazoa?

Phylum Mesozoa

How many cells and layers are in Phylum Mesozoa?

20-30, two

What are the two groups of Phylum Mesozoa?

Rhombozoans and orthonectids

Phylum Nemertea include

ribbon worms

How are Phylum Nemertea shaped?

thread or ribbon

Where do Phylum Nemertea live in?

gelatinous tubes made of self secreted material

What is a unique characteristic to Nemerteans

eversible proboscis

What is the symmetry of Phylum Nemertean?

bilateral, cylindrical, flattened

What is the true coelomic cavity called in Phylum Nemetea?

rhyncocoel

How many lobed brain in Phylum Nemetea?

four

Asexual reproduction in Phylum Nemertea by

fragmentation

What type of larvae does Phylum Nemertea have?

pilidium

What type of cell does Phylum Nemertea have?

flame

Does Phylum Nemertea have a respiratory system?

no

Does Phylum Nemetea have a blood vascular system?

yes

Where is the mouth in Phylum Nemertea located?

anterior and ventral

How does food move in Phylum Nemertea?

cilia moves food through intestine

How is digestion in Phylum Nemertea?

extracellular in gut lumen

How does Phylum Nemertea seize prey?

proboscis, which pulls into rhyncocoel

What type of circulatory system does Phylum Nemertea have?

true

Class Trematoda life cycle

miracidium penetrates snail > transforms into sporocyst > rediae > cercariae > penetrate final host > metacercariae

Digenean reproduction of schistosome does not include what?

Metacarcariae stage

Rhombozoans in Phylum Mesozoa

mollusc kidney parasites

Orthonectids in Phylum Mollusca

invertebrate parasites

What life cycle does not have the rediae stage?

schistosoma