Download Document

Kingdom
Animalia
Phylum Survey
Phylum Porifera (sponges)
Phylum Cnidaria (cnidarians)
Phylum Ctenophora (comb jellies)
Phylum Platyhelminthes (flatworms)
Phylum Nematoda (roundworms)
Covered in Lab 6
Sea anemone (Cnidaria)
with symbiotic fish
Phylum Ctenophora (comb jellies)
• Subkingdom Eumetazoa: have tissues
• Embryos with ectoderm, endoderm.
Diploblastic. Have epidermis, gastrodermis,
mesoglea.
• Member of Radiata: have radial symmetry, lack
___________
• Small group: 100 species
Phylum Ctenophora (comb jellies)
• Have mouth and anal pore (complete digestive
tract)
• Have comblike plates of fused cilia, used to
swim.
Phylum Ctenophora (comb jellies)
• Many are
________________
Importance
• Invasive species
– North American comb
jelly
– About 10 cm in length
– Predatory: eats small
fish and fish larvae.
• Introduced into Black Sea in ship ballast
• Now in Caspian Sea, some in Mediterranean.
Importance
• Detected in 1982
• By 1989 was ____%
of biomass in Black
Sea
• Destroyed $250
million/yr fishery
there.
Phylum Survey
Phylum Porifera (sponges)
Phylum Cnidaria (cnidarians)
Phylum Ctenophora (comb jellies)
Phylum Platyhelminthes (flatworms)
Phylum Nematoda (roundworms)
Covered in Lab 6
Sea anemone (Cnidaria)
with symbiotic fish
Eumetazoa: Bilaterian Acoelomates
• Bilateral symmetry
• Acoelomates: no body cavity, but 3
embryonic layers (ectoderm,
endoderm, mesoderm)
• Focus on Phylum Platyhelminthes
(flatworms)
Phylum Platyhelminthes (flatworms)
• 20,000 species. Most (75%) are
parasites. Others aquatic or soil
terrestrial habitats
Marine flatworm
Planaria
Phylum Platyhelminthes (flatworms)
• Dorsoventrally flattened
• Body solid: only cavity is __________
• Gut is incomplete (1 opening). Digestion
mainly intracellular.
Phylum Platyhelminthes (flatworms)
• Have head, organs. Pharynx: acts as
mouth and anus
Phylum Platyhelminthes (flatworms)
• Have excretory system (protonephridia,
containing flame cells)
• Control water content, excrete wastes thru
excretory pore
Phylum Platyhelminthes (flatworms)
• Lack ______________ system. All
cells must be close to gut or
epidermis to receive oxygen and food
(gut highly branched to aid this)
Phylum Platyhelminthes (flatworms)
• Monoecious (hermaphroditic): make both
eggs (in ovaries) and sperm (in testes).
Phylum Platyhelminthes (flatworms)
• Class Turbellaria (turbellarians)
• Class Trematoda (flukes)
• Class Cestoda (tapeworms)
Class Turbellaria (turbellarians)
• Free-living. 4500 species. Ex,
Dugesia (planarian)
• In lab #6
• ___________ help them move
• Have ocelli (eyespots),
statocysts (detect gravity).
Class Turbellaria (turbellarians)
• Includes gorgeous free-living marine worms
•
•
•
•
Class Trematoda (flukes)
Parasites. >10,000 species named.
Lack ____________ organs
Have digestive system, ovary, testis.
Oral sucker to hold onto host.
Class Trematoda (flukes)
• Life cycles complex. Often larvae in
snails, may have intermediate host,
adults in vertebrate host (usually)
Class Trematoda (flukes)
• Schistosomiasis:
caused by blood
fluke (Schistosoma)
• About 1/20 of global
human population
infected
• Kills 800,000
people/yr!
Class Cestoda (tapeworms)
• 3500 species named.
• Intestinal parasites of
vertebrate animals
• Lack sense organs as
adults, lack digestive
systems. Absorb ________
from host thru worm’s
body wall
Class Cestoda (tapeworms)
• Scolex (head) with hooks,
suckers to hang on
• Proglottids: segments
behind head
Class Cestoda (tapeworms)
• New proglottids produced by _________ just
behind scolex
• Each proglottid has testes, ovaries
• Sperm exit genital pore of one proglottid and
enter that of another
Class Cestoda (tapeworms)
• Fertilized eggs stored in _________ of
proglottid
• Eventually proglottids break off and are
passed out in feces
Class Cestoda (tapeworms)
• Beef tapeworm:
Adult in human
intestine
• Eggs passed,
hatch, crawl on
grass, eaten by
cattle
Class Cestoda (tapeworms)
• Larva encysts in
beef, eaten by
person
• Becomes adult
worm in small
intestine.
Class Cestoda (tapeworms)
• Beef tapeworm (1% of U.S. cattle infected)
A few too many tapeworms....
Class Cestoda (tapeworms)
• Tapeworm record (human): 10 m!
• All time: whale tapeworm (30 m long)
Pseudocoelomates
• Have body cavity (no peritoneum)
• Organs suspended in body cavity
• Cavity filled with ______ under pressure.
Gives shape to body, allows efficient
movement
Pseudocoelomates
• Cavity provides:
– 1) space for organs to grow or enlarge
(stomach after meal)
– 2) storage space (gametes, wastes)
Pseudocoelomates
• Lack circulatory system. Fluids moving in
pseudocoel move materials about
• Digestive tract ___________ (mouth, anus)
Pseudocoelomates
•
•
•
•
•
Phylum Nematoda (roundworms)
Phylum Rotifera (rotifers)
Phylum Gastrotricha (gastrotrichs)
Phylum Loricifera (loriciferans)
several others
Phylum Nematoda (roundworms)
• Ubiquitous. 12,000
named species, barely
explored.
• Bilateral symmetry,
unsegmented, ______
• Muscles run length of
body (motion side-toside or whiplike)
Phylum Nematoda (roundworms)
• Dioecious (separate
male and female
individuals)
• Have excretory
system: renette cells
and collecting tubules
Phylum Nematoda (roundworms)
• Intestine, anus
• Cuticle: flexible outer
covering
• Pharynx: muscular
chamber
• Excretory and genital
pores
Phylum Nematoda (roundworms)
• Importance:
– 1) role in food chains
– Abundant: spadeful of soil may contain 1
million nematodes
– Widespread: Found in all __________ on
Earth
Phylum Nematoda (roundworms)
• Importance:
– 2) human parasites
– Ex, Trichinella
(cause of
trichinosis)
– Juveniles burrow
into host muscles
(incl. heart muscle)
– Commonly
contracted by
eating undercooked
pork
Phylum Nematoda (roundworms)
• Trichinosis story
– Common in wild animals, incl. polar bears
– 1897: Swedish explorers in hydrogen balloon
– Were stranded without supplies when balloon
failed. Killed and ate polar bear, but raw since
had no fire
– Rescued, but _________ of trichinosis
Phylum Nematoda (roundworms)
• Importance:
– 2) human parasites
– Ex, hookworms
– Juveniles enter skin
(often feet), reach
lungs (gross part:
being “coughed
up”!), move to
intestine
– Affects about 25%
of humans!
Phylum Nematoda (roundworms)
• Importance:
– 2) human parasites
– Ex, pinworm
– Live in large intestine
(not too dangerous)
– Grossest part:
_________________
– Lesson: wash your
hands after using the
bathroom!
Phylum Nematoda (roundworms)
• Importance:
– 2) human parasites
– Ex, elephantiasis
– Juvenile worms
carried by mosquito
– Injected into host,
mature in lymph
nodes (lymph system
drains fluids from
tissues)
Phylum Nematoda (roundworms)
• Importance:
– 2) human parasites
– Ex, elephantiasis
– Buildup of worms
can clog lymph
system, so fluid
collects in body parts
Phylum Nematoda (roundworms)
• Importance:
– 3) plant pathogens
– Some nematodes can cause severe crop
damage
Phylum Nematoda (roundworms)
• Importance:
– 4) insect pathogens: useful for ___________
– Can infect some species of pest insects with
nematodes (can kill in few days)
Infected Colorado
potato beetle
Phylum Rotifera (rotifers)
• About 2000 species. Freshwater mostly.
• Small (50-500 micrometers), multicellular
• Corona on top of head. Cilia ring, used for
feeding and locomotion.
QuickTime™ and a Cine pak decomp ress or are nee ded to s ee this picture.
Phylum Rotifera (rotifers)
• Some species lack males. Females lay
eggs that develop into new females with
no fertilization (___________________).
Phylum Rotifera (rotifers)
• Importance: major group in freshwater
systems (abundant and widespread)
Coelomates:
Mollusks and
Annelids
Coelomates (Eucoelomates)
• Have body cavity
• Peritoneum present: from mesoderm,
• ______________
Phylum Mollusca (mollusks)
• Large: 110,000 described species (#2 behind
arthropods!)
• Bilateral symmetry
• Body usually has calcareous shell, muscular foot,
head
Phylum Mollusca (mollusks)
• Mantle: fold of tissue that wraps around body.
– Secretes shell
– Gills are specialized mantle portion to extract oxygen from
water
• Organs: stomach, heart, gills, etc.
Phylum Mollusca (mollusks)
• Often have radula in mouth
• Usually ____________.
Radula
Phylum Mollusca (mollusks)
• Circulatory system open. Heart 3 chambers (2 collect
blood from gills, one pumps to body)
• Coelom is cavity around heart.
Phylum Mollusca (mollusks)
• Excretory system: nephridia gather nitrogenous wastes
from coelom, discharge them into mantle cavity. Can
reabsorb valuable ___________ so they aren’t lost.
Phylum Mollusca (mollusks)
•
•
•
•
Class Bivalvia (bivalves)
Class Gastropoda (gastropods)
Class Polyplacophora (chitons)
Class Cephalopoda (cephalopods)