Transcript lect10-2cut

Kingdom
Animalia
Important phyla features
• 1) Evolution of tissues
– Present in all but one group (Phylum Porifera:
sponges)
– Called ________________.
– Animals with tissues (all other phyla) called
Eumetazoa.
Important phyla features
• 2) Evolution of symmetry
– Sponges lack definite _______________
– Radial symmetry: characterize Radiata (Phyla
Cnidaria and Ctenophora)
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Important phyla features
2) Evolution of bilateral symmetry
Other animal phyla have bilateral symmetry
Note dorsal/ventral, anterior/posterior
Note _____________: clustering of senses and
nervous system at one end of body
Important phyla features
• 3) Evolution of a body cavity
• Acoelomates: no ______________. Outside from
ectoderm, gut from endoderm, in-between from
mesoderm
Important phyla features
• 3) Evolution of a body cavity
• Pseudocoelomates: body cavity between
mesoderm and ________________
Important phyla features
• 3) Evolution of a body cavity
• Coelomates: body cavity (coelom) develops
within mesoderm. Organs suspended in it.
____________: epithelium cells lining coelom
Important phyla features
• 3) Evolution of a body cavity
• Problem: cavity needs circulation system (blood)
• Open system: blood dumped into _________ and
mixes with body fluids
• Closed system: blood kept within ___________
Important phyla features
• 4) Protostome vs. deuterostome development
• Paths of embryonic development: does _________
become mouth or anus?
Important phyla features
• 4) Protostome vs.
deuterostome
development
• Other: cleavage
pattern, ____________
formation
• Also: any cell in
deuterostome embryo
can develop into
complete organism,
but not protostome
Important phyla features
• 5) Segmentation
• Divide body into sections along its length
– allows ______________ of systems (damage to
one not fatal)
– allows greater movement complexity as ________
expand/contract/interact
Phylogeny of animals
• Uncertain
Subkingdoms
• 1) Parazoa: Lack symmetry, lack ____________
– Phylum Porifera (sponges)
• 2) Eumetazoa: Have definite shape and
symmetry. Have tissues, and usually these
organized into organs (groups of tissues with
specific structure and function)
– Radiata: Have 2 embryonic layers. Ectoderm (outer)
and endoderm (inner). ___________________.
– Bilateria: Have 3 embryonic layers: Ectoderm,
endoderm, and mesoderm (middle layer).
_____________.
Phylum Survey
Phylum Porifera (sponges)
Phylum Cnidaria (cnidarians)
Phylum Platyhelminthes (flatworms)
Phylum Nematoda (roundworms)
Covered in Lab 6
Sea anemone (Cnidaria)
with symbiotic fish
Phylum Porifera
• Parazoa: Lack symmetry, lack _____________
• About 5000 species, almost all marine
• Larva (immature stage) swims, adult is sessile
(attached to ocean bottom)
• Have multiple cell types, but little ___________
among cells
“Glass” sponges from 1400 feet down
Phylum Porifera
• Osculum: large opening
• Water flows thru pores, driven by __________ of
choanocytes
Phylum Porifera
• Collar of choanocytes traps food particles
(ingested by cell)
• Digestion __________________
• Spicules (hard) and spongin (spongy) fibers
Phylum Porifera
• Spicules and spongin fibers
(protein): give body shape
and protection
Spicules
Phylum Porifera
• Other cells:
– epithelium
– pore
– amoebocyte (move about and secrete spicules and
spongin fibers)
Phylum Porifera
• Other cells obtain food by transfer from
_______________
• Note spongocoel: large internal cavity. NOT a true
digestive cavity since digestion intracellular.
Phylum Porifera
• Body complexity
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–
–
–
1) simple (Scypha)
2) intermediate
3) complex (common)
Note spongocoel and where
choanocytes located in each type.
Scypha sponges
Phylum Porifera
• Reproduction:
• Asexual by _____________.
Can pass some sponges
through silk mesh and they’ll
reform!
• Sexual: some _____________
make sperms and eggs, these
then make swimming larva
• Larva settles and starts to
grow into mature sponge.
Phylum Porifera
• Sponge importance/uses:
• Original source of ________ sponges
Greek sponge fishermen
and processors (Mediterranean
Sea)
Phylum Porifera
• Sponge importance/uses:
• Consumers/habitat feature in marine _________
• Some contain potentially useful chemicals
– some toxic to fish and used as insecticides
– HIV treatment? One sponge chemical interferes with
HIV virus
– Cancer treatment? ______________: compounds
that inhibit tumor growth
Sponge inhabited
by crab
Phylum Cnidaria (cnidarians)
• Subkingdom Eumetazoa: have tissues
• Embryos with ectoderm (becomes epidermis
tissue and nerves) and endoderm (becomes
digestive tissue: gastrodermis). _____________.
• Note no mesoderm.
Phylum Cnidaria (cnidarians)
• Have mouth and digestive (gastrovascular)
cavity. Extracellular digestion (can eat big
things!). Incomplete digestive tract (no anus).
• ____________ is tissue (produced by ectoderm)
between epidermis and gastrodermis that
contains muscles
• Member of Radiata: have radial symmetry, lack
organs
Phylum Cnidaria (cnidarians)
• Almost all marine. About _________ species.
• Carnivores. Capture prey with stinging
tentacles.
QuickTi me™ a nd a Cinep ak decompre ssor are n eede d to see thi s pi ctu re.
Phylum Cnidaria (cnidarians)
• Body forms: polyp (sessile) and medusa
(swimming)
• Each with gastrodermis, epidermis, mesoglea
Phylum Cnidaria (cnidarians)
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Many have polyps and medusae as parts of life cycle
Make swimming planula larva
Example: Obelia
Note asexual reproduction of polyps by _________
Phylum Cnidaria (cnidarians)
• Body structure of polyp (Ex, Hydra)
• Note digestion is extracellular (outside of
individual cells) in gut cavity. Individual cells
ingest food particles by ________________.
Phylum Cnidaria (cnidarians)
• Tentacles with stinging cells (cnidocytes).
• Cnidocytes contain ______________ (harpoon)
Class Hydrozoa (hydroids)
• Usually with polyp and medusa stages
• Exs, Obelia (marine), Hydra (freshwater)
• Bottom view of medusa of Obelia, with
_____________, mouth visible.
Class Hydrozoa (hydroids)
• Ex, Portuguese man-of-war
• Colony of four types of polyps
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float polyp
feeding polyps
tentacle polyps
gamete polyps
Class Scyphozoa (jellyfish)
• Only about 200 species, _____________
• Medusa stage largest part of life cycle
Swim using
contractions of
bell
QuickTi me™ a nd a Cinep ak decompre ssor are n eede d to see thi s pi ctu re.
Class Scyphozoa (jellyfish)
• Anatomy
Class Cubozoa (box jellyfish)
• Similar to jellyfish, but tentacles at end of boxshaped body
• Small group: 20 species.
Class Cubozoa (box jellyfish)
• Can be deadly. Ex, Australian
stinger.
• Nematocysts packed into rings
on tentacles.
• 100 deaths in last century due
to extensive stings
Class Anthozoa (sea anemones/corals)
• Largest cnidarian group (6200 species), marine
• Sea anemones:
– Have only _________ stage.
– Solitary (don’t form colony).
– Make no exoskeleton.
Class Anthozoa (sea anemones/corals)
• Body a tube: oral disk (with mouth) surrounded by
tentacles, pedal disk attaches tube to bottom
• Pharynx and gastrovascular cavity process ______.
Class Anthozoa (sea anemones/corals)
• Sea anemone symbionts
– anemonefishes (28 species): not stung (due to ______
on fish body). Can be species-specific.
Class Anthozoa (sea anemones/corals)
• Sea anemone symbionts
– some have algae living in tissues (zooxanthellae)
– can give anemone color
– deep sea anemones lack these.
A deep sea anemone
The submersible,
Alvin
Class Anthozoa (sea anemones /corals)
• Corals:
– Also have only polyp stage but are _____________.
– Many secrete exoskeleton of calcium carbonate (stony
corals).
Class Anthozoa (sea anemones/corals)
• Corals: Help form coral reefs.
Class Anthozoa (sea anemones/corals)
• Stony corals: Have exoskeletons, and many
tentacles per polyp.
Class Anthozoa (sea anemones/corals)
• Soft corals: Do not have exoskeletons. Have
only ______ tentacles per polyp.
Class Anthozoa (sea anemones/corals)
• _________ examples include gorgonians, leather
Leather corals (3 ft tall)
corals, and sea pens
Sea
pens
Gorgonians
Coral Reefs
• Diverse: maybe 1-3
million species present
• 30% of ocean fish
species, ______% of
ocean area
• High productivity
• Marine “__________”:
many fish spend some
time (including larval
stages) at reefs.
Coral Reefs
• Recall coral biology: polyps contain
photosynthetic dinoflagellate algae
(zooxanthellae)
• Algae produce up to ______% of energy used
by polyp.
Coral Reefs
• Unusually warm
water may cause
corals to expel
_________________
• “Bleached” coral
may die
• 1998 El Niño Event:
warm water
widespread in
Tropics.
A bleaching coral from Micronesia
Coral Reefs
• 1998 El Niño event
– Indian Ocean: up to 85% coral mortality
– Great Barrier Reef (Australia): 87% of inshore
reefs bleached
– Florida Keys: 40-90% of reefs bleached.
Coral Reefs
• Many other threats:
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Global climate change
Pollution
Sedimentation
Overharvesting
Blasting (dynamiting):
fishing technique
Coral Reefs
• Many other threats:
– ________ fishing: capture
fish for aquarium trade or
for live food fish in
oriental markets
Coral Reefs
• 2002 report (Status of The Coral Reefs of
the World 2002)
– 27% of reefs already severely
damaged/destroyed
– 14% more expected to be severely
damaged/destroyed in next 10-20 years
• August 2003 article (in journal: Science)
– 30% of coral reefs severely damaged
– 60% projected severely damaged by 2030.
Phylum Ctenophora (comb jellies)
• Subkingdom Eumetazoa: have ____________
• Embryos with ectoderm, endoderm. 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 __________, 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 Platyhelminthes (flatworms)
Phylum Nematoda (roundworms)
Covered in Lab 6
Sea anemone (Cnidaria)
with symbiotic fish
Eumetazoa: Bilaterian Acoelomates
• Bilateral symmetry
• Acoelomates: no ___________, 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)
• Body solid: only cavity is __________
• Gut is incomplete (1 opening). Digestion
mainly _________________.
• Have head, organs. Pharynx: acts as
mouth and anus
Phylum Platyhelminthes (flatworms)
• Have __________ 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)
• ______________ (hermaphroditic): make both
eggs (in ovaries) and sperm (in testes).