Biological Principles II
Animal Flashcard Activity (Invertebrates)
We’re going to begin with all of our animal flashcards. ese are flashcards #62-110, plus #12.
at was our stand-in for the animals when we were first diving into the eukaryotes.
12.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
toucan
turtle
coelacanth
sponge
salamander
coral
barnacles
planarian
grasshopper
sea star (starfish)
peacock
elephant
tapeworm
74.
75.
76.
77.
78.
79.
80.
81.
82.
83.
84.
85.
86.
sailfish
cheetah
earthworm
cuttlefish
ctenophore
human
lungfish
quahogs
squid
spider
horseshoe crab
dragonfly
honeybee
87.
88.
89.
90.
91.
92.
93.
94.
95.
96.
97.
98.
99.
sponge
penguin
crab
sea urchin
tunicates
snake
lancelet
jellyfish
koala
hagfish
snail
gorilla
shark
100. sea anemone
101. polychaete worm
102. lamprey
103. manta ray
104. nematode
105. clownfish
106. orca (killer whale)
107. frog
108. platypus
109. crocodile
110. chipmunk
GETTING READY
1. Start with all of your flashcards spread out in front of you. Ideally, they aren’t overlapping, but
that will depend on how much space you’re working with.
2. e entire group of organisms in front of you constitutes the animal kingdom. Animals form
a monophyletic group called the metazoans (or Metazoa).
METAZOA > PORIFERA (Sponges)
3. Begin by pulling out the sponges (#64 and #87) and placing them off by themselves.
Sponges:
are generally considered to be the most primitive of all animals.
lack true tissues.
lack symmetry.
are essentially colonies of choanoflagellates (#5)
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METAZOA > EUMETAZOA > RADIATES (Cnidarians and Ctenophores)
4. Now that the sponges have been separated off, the remaining animals are called eumetazoans
(eu– = true, so these are “true metazoans”). Eumetazoans have cells organized into specialized
tissues, such as muscle, nervous tissue, connective tissue, and epithelial tissue.
5. Next, separate out #66, 78, 94, 100.
ese organisms have two important advancements not seen in sponges:
Cells that are organized into two tissue layers (ectoderm and endoderm). erefore, they
are diploblasts.
ey have radial symmetry (and are sometimes referred to as radiates).
Cnidarians
Ctenophores
Jellyfish:
Sea anemone:
Coral:
Comb jelly:
• Displays the medusa
body plan
• Displays the polyp
body plan
• Colonies of polyps
that excrete a
mineralized wall;
many types have
photosynthetic algae
as endosymbionts.
• Planktonic
organisms that move
via rows of cilia
called ctenes.
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METAZOA > EUMETAZOA > BILATERIA
6. e remaining animals share two important characteristics:
ey have bilateral symmetry (and are therefore called bilaterians).
eir bodies are composed of three tissue layers: endoderm, mesoderm, and ectoderm.
ese organisms are triploblastic.
7. Originally, morphologists grouped the bilaterians based on their developmental patterns, as
shown below. Recreate these groups with your flashcards.
Protostomia (protostomes)
Deuterostomia (deuterostomes)
ese animals follow the protostome pattern of
development, in which the blastopore forms the
animal’s mouth.
ese animals follow the deuterostome pattern of
development, in which the blastopore forms the
anus. (e mouth forms later.)
67, 68, 69
73, 76, 77
81, 82, 83, 84, 85, 86, 89
97
101, 104
12
62, 63, 65
70, 71, 72, 74, 75, 79
80, 88
90, 91, 92, 93, 95, 96, 98, 99
102, 103, 105, 106, 107, 108, 109, 110
8. is classification scheme persisted for decades until molecular biologists used DNA
sequence analysis to revisit the bilaterians. ey found that, while the deuterostomes were
clearly related to each other, the protostomes were not, with some protostome groups as
related to the deuterostomes as they were to other protostomes. In the end, they disbanded
Protostomia and reapportioned the protostomes into two new groups: the Lophotrochozoa
and the Ecdysozoa.
9. Regroup your protostome flashcards into the two groups shown below:
Protostomia (protostomes)
disbanded
Lophotrochozoans
68
73, 76, 77
81, 82
97
101
Ecdysozoans
67, 69
83, 84, 85, 86, 89
104
Deuterostomia (deuterostomes)
(left unchanged)
12
62, 63, 65
70, 71, 72, 74, 75, 79
80, 88
90, 91, 92, 93, 95, 96, 98, 99
102, 103, 105, 106, 107, 108, 109, 110
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METAZOA > EUMETAZOA > BILATERIA > LOPHOTROCHOZOA
e lophotrochozoans are an incredibly anatomically-diverse group. As stated above, they are
grouped together based on DNA sequences and named for two features observed in most
members:
a lophophore – a crown of cilia used for feeding
a trochophore larval stage
10. Arrange your flashcards into the three major groups of lophotrochozoans:
Platyhelminths (flatworms)
Annelids (ringed worms)
• Lack coeloms
• eir bodies consist of repeating
units, usually with the same
anatomical structures repeated in
each unit.
• Very thin; rely on diffusion for
most transport processes
• Some are free-living, while others
are parasitic
Molluscs
Bivalves:
Gastropods:
Cephalopods:
• Have two hinged shells
(called valves)
• Have two hinged shells
(called valves)
• Incl. clams, mussels, and
scallops.
• Incl. snails, slugs, and
nudibranchs.
• Most of these have lost their
shells (or have greatly-reduced
shells).
• Bivalves draw water into
their bodies via siphons and
feed on particles.
• eir bodies undergo
torsion, a twisting process,
during development. (is is
not related to the twist in
their shell.)
• Cephalopods are active predators,
with tentacles to catch prey.
• ey have acute senses and
impressive cognitive abilities.
• ey shoot water out of siphons
to propel themselves.
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METAZOA > EUMETAZOA > BILATERIA > ECDYSOZOA
e ecdysozoans are the most numerous of the animal groups. ey account for more than 75%
of known animal species.
Again, as with the lophotrochozoans, they are grouped together based on DNA sequence
information.
All ecdysozoans have a hard covering that must be molted in order for the animal’s tissues
to grow. e process of molting is called ecdysis, hence the name of this group.
11. Arrange your flashcards into the two main ecdysozoan groups:
Nematodes
(roundworms)
• Small worms without segments
• Most are freeliving in soil and
damp environments.
• Some are parasitic.
Arthropods
Crustaceans:
Chelicerates:
Insects:
• Incl. crabs, shrimp, lobsters, and
barnacles.
• Incl. spiders, ticks, mites,
scorpions, and horseshoe crabs.
• Incl. bees, wasps, butterflies, dragonflies,
mosquitoes, beetles, and cicadas, among others.
• Tiny crustaceans called krill are
consumed in large quantities by
large marine organisms, such as
whales.
• Named for fanged mouthparts
called chelicerae.
• Many members of this group have evolved
flight by producing wings from the outer
covering of their exoskeleton.
• Some (such as spiders and
scorpions) have toxins for
immobilizing prey.
• Spiders spin silk strands for
making webs, protecting eggs, or
making filaments to fly away.
• Many have acute vision through the use of
compound eyes.
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METAZOA > EUMETAZOA > BILATERIA > DEUTEROSTOMIA > ECHINODERMATA
12. All of your remaining flashcards cover the deuterostomes.
13. Separate out #70 and #90. ese are the echinoderms:
eir name comes from the fact that they have a thin skin that covers calcium plates with
knobs and protrusions, giving them the appearance of “spiny skin.”
While all adults have imperfect radial symmetry, these animals are still considered
bilateral because they have fully bilaterally symmetrical larvae.
A notable feature of echinoderms is that they possess a series of seawater-filled tubes
through their bodies called a water vascular system. is water vascular system is used to
both transport materials throughout their bodies, as well as locomotion.
is group includes the sea stars (#70), sea urchins (#90), sand dollars, brittle stars, and
sea cucumbers.
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