Download Today:

Who am I?
Thoughts on the Burgess Shale?
Today:
Pass or Play
a.
Review of Protozoans
Animal Survey Continued
b.
Into the Vertebrates?
c.
d.
A Diplomonad/
Diplomonad/
Parabasala
A Euglenozoa
An Alveolata
None of the above
Winter College Transfer Fair! Thursday, February 10, 2005
9:00am - 12:30pm
Shark Talk! Friday, 2/11, 10:30 am (Location TBA)
Mode of Nutrition?
a.
b.
c.
d.
Heterotrophic
Photoautotrophic
Mixotrophic
Chocolatrophic
Who am I?
a.
b.
c.
d.
Who am I?
I’m distinguished, in part, by my…
a.
b.
c.
d.
Lack of
Mitochondria
Unusual set of
DNA packaged
with my
mitochondria
Parasitic lifestyle
Two, haploid nuclei
A Diplomonad/
Diplomonad/
Parabasala
A Euglenozoa
An Alveolata
None of the above
a.
b.
c.
d.
A Diplomonad/
Diplomonad/
Parabasala
A Euglenozoa
An Alveolata
None of the above
1
Who am I?
I’m distinguished, in part, by my…
a.
b.
c.
d.
e.
Lack of Mitochondria
Unusual set of DNA
packaged with my
mitochondria
Parasitic lifestyle
Two, haploid nuclei
a and d
a.
b.
c.
d.
A Diplomonad/
Diplomonad/
Parabasala
A Euglenozoa
An Alveolata
None of the above
True or False?
Where
we’ve
been…
I use pseudopodia for
feeding.
A = True
B = False
The Nematodes (Roundworms)
„
„
Digestive tract complete
Pseudocoelom
Ascaris:
The Annelids (Segmented worms)
„
„
„
„
Trichinella:
„
True Coelomates (+ all animals beyond)
Annilids are schizocoelous
Closed circulatory system
Nervous system, oneone-way gut Earthworm
Primarily freefree-living
(Lumbricus):
Vinegar Eels:
Leeches:
2
The Development of the Coelom
Planaria
Ascarics
Lumbricus
Acoelomate
Pseudocoelomate
Eucoelomate
The Arthropods
„
„
„
„
„
Segmented body, covered by exoskeleton
Typically divided into 3 tagmata:
tagmata: the head,
thorax, and abdomen
Open circulatory system w/heart
Reduced coelom
WellWell-developed nervous system
Arthropod Diversity:
Chelicerates
„
Horseshoe Crabs,
scorpions, ticks and spiders
„
All have unique feeding
appendages called
The Molluscs
„
„
General body plan includes the foot, the visceral
mass, and mantle
Open circulatory system with chambered heart
The Arthropods:
Enormous Diversity!
DNA evidence supports 4 major
lineages:
1. The Trilobites
2. The Chelicerates
3. The Uniramians
4. The Crustaceans
Arthropod Diversity: Chelicerates
chelicerae
3
Arthropod Diversity: Uniramians
Arthropod Diversity: Uniramians
Centipedes, millipedes and insects
Have uniramous (unbranched)
unbranched) appendages
„
„
Arthropod Diversity: Crustaceans
Crabs, lobsters, shrimp, barnacles
Usually have biramous appendages
„
„
The Echinodermata
„
„
„
„
„
Deuterostomes!
Deuterostomes!
5-part body plan
Water vascular system w/tube feet
Bilateral larvae w/ “radial” adults
Spiny skin, internal skeleton
Leaving the
Protostomes
I’m so confused.
Am I radial or
bilateral??
4
The Chordates
Phylum includes sea squirts
(tunicates), lampreys and
hagfishes, fishes, amphibians,
reptiles, birds and mammals
The Chordates
The Chordates
4 Common Features:
1. Flexible supporting skeletal rod called a
notochord
2. Dorsal hollow nerve cord above the
notochord
3. Pharyngeal pouches in the pharynx
4. Post anal tail
A Segmentation Sidetrack…
Segmentation shows up in some of the lophotochozoans
(annelids), ecdysozoans (arthropods) and
deuterostomes (chordates).
What does parsimony suggest??
The Chordates: The Urochordata
Tunicates:
•No backbone
The Chordates: The
Cephalochordata
Amphioxus:
•Larval form has all four traits; Sessile adult looks
nothing like a chordate!
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The Aquatic Vertebrates
The Chordates: The Vertebrates
„
„
„
A bony spinal or vertebral column replaces the
notochord, and encases the dorsal nerve cord
Skull surrounds the brain
Can be divided into Aquatic, Transitional, and
Terrestrial Vertebrates
The Transitional Vertebrates
(Amphibians)
„
„
„
Oldest= Jawless fish
May have cartilaginous or bony skeleton
Terrestrial Vertebrates
„
Incompletely adapted to terrestrial environments
Reptiles, birds (Aves) and Mammals
Why do I
feel so
incomplete?
Vertebrate
Ancestors:
Hagfish
(Slime Eels)
„
„
„
„
Agnathans (“without jaws”)
Cartilage skeleton including a cranium
(skull)
No vertebrae (so not true vertebrates??)
No paired fins, teeth or hardened
bones
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Lampreys in the
News…
Vertebrate
Ancestors:
Lampreys
„
„
„
Sea lamprey 'love signal' may tame
species
April 4, 2002 Posted: 3:28 PM EST (2028 GMT)
By Alex Walker
CNN SciSci-Tech
Cartilaginous “pipe” surrounds the notochord
and partially encloses the nerve cord
No true jaw or paired fins
No ossified bones
EAST LANSING, Michigan (CNN) -- Male sea
lampreys -- eeleel-shaped fish that use their suctionsuctioncup mouths to extract body juices from other fish - excrete a chemical during spawning that acts as a
powerful sexual comecome-on, scientists at Michigan
State University say in the journal Science this
week
The Transition
to True
Vertebrates
Evidence from the
fossil record:
Ostracoderms
(“shelled skin”) have
ossified armor of
bony plates
Major Vertebrate Characteristics
1.
2.
3.
4.
Neural Crest
Heavy Cephalization
A Vertebral Column
Closed Circulatory System
Thursday: Finishing the
Vertebrates
Cells from the neural crest of a 9 day mouse;
www.med.unc.edu
In the meantime…
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Some Review…
I am a ___________________
(common name and phyla)
Some Review…
I am a ___________________
(common name and phyla)
My Choanocytes are important
because they ____________
I have specialized cells for
capturing prey called
____________
True or False:
True or False:
I have true tissues.
I can only reproduce asexually.
Some Review…
I am a ___________________
(common name and phyla)
True or False:
I have a true coelom.
I have a complete digestive
tract.
I am triploblastic (have 3 germ
layers).
Some Review…
I am a ___________________
(common name and phyla)
True or False:
I have a oneone-way digestive
tract.
I have a heart and closed
circulatory system.
I am a pseudocoelomate.
pseudocoelomate.
I am triploblastic.
triploblastic.
I have a gastrovascular cavity
with a single opening.
Some Review…
I am a ___________________
(common name and phyla)
True or False:
I have a digestive tract with a
single opening.
I am a pseudocoelomate.
pseudocoelomate.
I am triploblastic.
triploblastic.
A Question…
Why do earthworms
always end up on the
sidewalk after a heavy
rain??
(Generate a hypothesis with
your group!)
8
Group Task: Which one of these
does not belong? (Why?)
Some Review…
I am a
_________________
(common name and phyla)
True or False:
Snails and Octopuses are also in by phylum.
I’m radially symmetrical.
The three body parts I share with other members of
my phylum are the ______, ______, and _______.
Some Review…
I am a
_________________
(common name and phyla)
True or False:
I am triploblastic.
I don’t have a true body cavity (acoelomate).
My body is completely covered by a rigid
___________ that provides ________________.
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