Echinoderms and chordates

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Echinoderms and chordates
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Announcements
There will be a quiz next lab period Assignment
for this lab include pages 95, 96, 97, 98, 99
100, 101.
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Group project
-Choose your group (usually 4) -Start to out-line
(Project proposal-worth 5 points) 1-Hypothesis or
question you want to ask with some back
groud informations and justification 2-How you
are going to test this hypothesis or solve this
question (number of samples, type of
data) 3-What kind of statistical analysis you
will perform 4-The oral presentation must be in
powerpoint format
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This lab

• Why they are grouped together
• Different Echinoderms
• Different Chordates
• Dissecting two distantly related chordates

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Echinoderms and chordates
They are grouped together b/c 1- they are
metazoans 2-deuterostome mode of development
3-enterocoelom out-pocketing of the gut into
mesoderm layer
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Echinoderms
1-exclusively marine 2-internal skeleton
(calcareous with protruding spines on the
surfacespiny skin) 3-coelomic cavity forms a
water-vascular system 4-tube feet (extension of
coelomic canals with suction pads) 5-radial
symmetry 6-male female 7-gas exchange through
body wall or tube feet. 8-ciliated larvae
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Echinoderms
1-Crinoidea (feather star) -primitive
-filter feeders -feathery arms 2-Asteroidea(sea
stars) - 5 arms or more -carnivores
3-Ophiuroidea(brittle star) -long arms (snake
stars) -more mobile by crawling
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Echinoderms
4-Echinoidea(sea urchins) -covered with spines
-no arms -solid skeletal encasement
-scraping teeth (feed on algae) 5-Holothuroidea(se
a cucumbers) -no arms -few calcareous plates
-no spines -body elongated
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Chordates
1- gills slits 2-notochord 3-dorsal hollow nerve
tube 4-post-anal tail 4-metamerism (segmentally
arranged blocks of muscles) 5-bilateral
symmetry The world is numerically dominated
by invertebrates and microorganisms
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Chordates
1-Urochordata or tunicates(sea squirts) -show
the derived character only during larval
stage -notochord metamerism are in the
tail 2-Cephalochordata(amphioxus) -adults show
the derived characters -notochord extend to the
head 3-Vertebrata a-Fish paraphyletic group
contain 5 classes b-class Amphibians(frogs)
-tetrapod -lungs
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Chordates
C- class Reptilia paraphyletic group of 5
differentiated based on the presence or absence
of openings in the temporal bone D-class
Aves E-class Mammalia -mammary gland -4
chambered heart -synapsid skull -variable
teeth -complete diaphragm -endothermy
-large brain P.s. the ancestor of the last 3
classes share 1-shelled eggs or viviparity
2-amniotic egg
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Class Mammalia
1-order Carnivora (cat) 2-order Perissodactyla
(horse) 3-order Artiodactyla (cow) 4-order
Cetacea (dolphins) 5-order Rodentia (rat and
mice) 6-order primates (human)
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Anatomy of the fore-limb in horse and human
1-Scapula 2-Humerus 3-Radius and
Ulna 4-Carpus 5-Metacarpus 6-Phalanges
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What should I do now
1- dissect frog and/or rat 2-demo 3-answer the
questions 4-ask if there is uncertainty