Transcript The Worms! - Conackamack Middle School

The Worms!
Three Phyla of Worms
• Flatworms – Phylum Platyhelminthes
• Roundworms – Phylum Nematoda
• Segmented worms – Phylum Annelida
Worm Body Characteristics
• Body Symmetry: bilateral
• Cell Organization: cells to tissues to organs to
SIMPLE organ systems
• Reproduction: sexual/asexual (regeneration)
• Body Development: zygote to egg to cocoon to
adult
The Flatworms
• Over 10, 000 species
• Flat bodies
• Most are parasites
– Tapeworms
– Liver flukes
• Non parasitic types
– Planarian
Tapeworms are Parasites
• Can live in humans, dogs, cats, horses,
pigs, and other pets.
• Step 1: the larvae is ingested (ex.
eating pork that was infested with the
tapeworm eggs)
• Step 2: Larvae grows into a worm and
hooks onto the intestine wall
• Step 3: Tapeworm feeds off of food in
the intestines; grows larger and larger
• Step 4: Eggs leave through the feces of
the host and the eggs can be ingested
by another animal.
How Do You Get rid of a Tapeworm?
• Medicines can kill the worm and
the host gets rid of the worm in
tiny pieces through its feces.
• Worm can be “coaxed” out
through the mouth or anus.
• Worm can be pulled out through
a small incision in the skin.
The longest tapeworm ever
removed from a human
came out of Sally Mae
Wallace on September 05,
1991. In all, doctors pulled 37
feet of tapeworm out of Sally
Mae Wallace's body through
her mouth.
If you find all of this
disgusting, be glad you're not
a whale as tapeworms in
whales can grow up to 120
feet long.
The Roundworms
• Cylindrical bodies
• One-way digestive system
• Some are parasites
Tubeworms
grow on ocean
thermal vents.
They grow from
both ends!
Raccoon
roundworms
Ascaris roundworm
Found only in humans where there
are unsanitary conditions and poor
plumbing. Roughly 1 in 6 people
worldwide are infected. Eggs hatch
and bore through intestine walls.
The worm then moves to the heart,
the lungs and then OUT the
breathing passages.
The Segmented Worms
• Bodies are long and
narrow
• Made up of many
linked sections
called segments.
• Exs. – leeches,
earthworms, bristle
worm
Earthworms
help to aerate
soil and
increase plant
growth.
Leeches
can be
used for
medicinal
purposes
The Segments
• Many organ systems run through all the
segments
– Digestive system, nervous system, circulatory
system
• Others are found only in certain areas
– Reproductive system
How Do Some Worms Reproduce?
• Asexual Reproduction
– Regeneration: the regrowth of an organ, tissue,
or part that has been lost
or destroyed
Sexual Reproduction In Earthworms
HOW EARTHWORMS LIVE
• They tunnel for a living
• They are scavengers
– Eat the decayed remains of plants
and animals
• Earthworms come out mostly at
Who am I? I am a giant
night.
earthworm
Where do I live? I burrow
– The ground is damp
deep into the wet earth of the
rainforest
– Most predators are asleep
What do I eat? Leaf litter and
• Worms get their oxygen through their dirt
What do I do? I grow up to a
damp skin.
meter long and I am bright
blue
– If they dry out they will die
What is special about me?
My spit glows in the dark
How Do Earthworms
Move?
• The worms have welldeveloped muscles that
allow them to burrow
• Bristles (setae) are found
on each segment and
stick into the ground.
How Are Earthworms Beneficial?
• Improve the soil in which
plants grow.
• Earthworm droppings
make the soil more fertile.
• Earthworm tunnels loosen
the soil and allow air,
water and plant roots to
move through it.
• Earthworms are
decomposers and can be
used in compost piles.