FlatWorms and Pseudocoelomates

Created by LiveWire421 

Upgrade to
remove ads

Cephalization

An evolutionary trend toward the concentration of sensory equipment at the anterior end of the body.

Acoelomate

A solid-bodied animal lacking a cavity between the gut and outer body wall.

Pseudocoelomate

An animal whose body cavity is not completely lined by mesoderm

Monogenetic

a parasitic flatworm having one host in its life cycle

Digenetic

a parasitic flatworm having two hosts in its life cycle

Monoecious

having male and female reproductive organs in the same plant or animal

Dioecious

having male and female reproductive organs in separate plants or animals

Diploblastic

Having two germ layers.

Triploblastic

has three germ layers: the ectoderm, endoderm, and mesoderm.

Phylum Platyhelminthes

Phylum ???

---flattened, unsegmented worms, exhibit bilateral symmetry ---cephalization

Class Tubellaria

Phylum Platyhelminthes / Class ???

---free-living flatworms
---Dugesia(aka planaria)
---inhabits freshwater, saltwater and moist terrestrial env.
---carnivores ----hermaphroditic
---have auricles, ocelli, pharynx, and mouth

Class Cestoda

Phylum Platyhelminthes / Class ???

---tapeworms
---parasites of vertebrates
---no head or digestive systems
---life cycle with one or more intermediate hosts in which
larvae develop (Digenetic)

Scolex

head of an adult tapeworm; can contain suckers or hooks

proglottids

One of the segments of a tapeworm, containing both male and female reproductive organs

Class Trematoda

Phylum Platyhelminthes / Class ???

---flukes
---they are parasites
---complex life cycles with alternating sexual and asexual stages, those that parasitize humans spend part of lives in snail hosts

Human Liver Fluke Life Cycle

1) Miracidium 2) Sporocyst 3) Redia 4) Cercaria

Miracidium

1) First Stage of Fluke Life Cycle
---is the free swimming, ciliated larva which emerges from the trematode egg and swims about in search for the first intermediate host (eg. snail)

Sporocyst

2) Second Stage of Fluke Life Cycle
---a saclike larval stage in the life cycle of some trematodes, which develops from a miracidium and produces several rediae

Redia

3) Third Stage of Fluke Life Cycle
---trematode larval stage that reproduces asexually to produce cercariae
---Final Stage before reaching maturity

Class Monogenea

Phylum Platyhelminthes / Class ???

---fluke
---life cycle includes one host
---mainly ectoparasites
--- tegument
---hooks on anterior and posterior ends for attaching to host

Phylum Acanthocephala

Phylum ???

---phylum of elongated wormlike parasites that live in the intestines of vertebrates
---spiny-headed worms
---dieocious (separate sexes)

Phylum Rotifer

Phylum ???

---pseudocoelum
--- bilateral symmetry
--- 3 germ layers,
---complete gut
--- corona(Crown)
--- foot w/ cement gland, dioecious (separate sexes)

Corona

(anatomy) any structure that resembles a crown in shape, Seen in Rotifers.

Cilia

short structures projecting from a cell and containing bundles of microtubules that move a cell through its surroundings or move fluid over the cell's surface

Auricles

ear-like projections on a flatworm that are sensitive to chemicals and touch

digenetic

having two types of multiplication in two or more hosts. Sexual, occurs in adult or mature stage within definitive host, asexual, occurs in larval stages within intermediate host(s); velonging to subclass of trematodes Digenea (all flukes of human and veterinary importance belong to this Order) Direct life cycle - only one host required in life cycle but part of life cycle may be in the enviornment

tegument

a natural protective covering of the body

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set