Ingest their food, lack cell walls, muscles and nerve cells, reproduce sexually, development is governed by a unique conserved genetic network
Characteristics of Animals
Cambrian period
When were most animal phyla on Earth
lack of tissues; individual cells act independently
What separates sponges from all other animals
groups of similar cells integrated into a functional unit
what are tissues
asymmetrical
sponges symmetry
cylindrical or spherical with the body organization arrayed around a central point, like slices of a pie
radial symmetry
one plane can divide organism into mirror image halves
bilateral symmetry
2, diploblasts have two embryonic germ layers of cells: endoderm and ectoderm
radial symmetrical animals have how many embryonic tissue layers
3, triploblasts have three embryonic germ layers of cells: endoderm, mesoderm and extoderm
bilateral symmetrical animals have how many embryonic tissues layers
inner layer which gives rise to tissues that line the gut cavity
endoderm definition
hollow organs, respiratory surfaces and gut
what does the endoerm form
the outer layer which gives rise to the tissues that cover the outside of the body
ectoderm
nerve tissues and tissue on the outer surface of the body
what does the ectoderm form in bilateral animals
lies between the endoderm and the ectoderm
mesoderm
muscles, circulatory and skeletal systems
what does the mesoderm form in bilateral animals
fluid-filled cavities between the digestive tube and the outer body wall found in bilateral animals
body cavities definition
wihtout a coelom or body cavity
acoelomate definition
Psuedocoelomate; an animal whose body cavity is lined by tissue derived from mesoderm and endoderm.
blastocoelomate definition
An animal that possesses a true coelom (a body cavity lined by tissue completely derived from mesoderm).
coelomate definition
all animals had coeloms but eventually lost it
how did acoelomates and blastocoelomates evolve
flatworms; platyhelminthes
acoelomate animals
roundworms; nematodes
pseudocoelomate animals
annelids, chordates
coelomate animals
(E)
blastopore definition
(B)
the fluid-filled cavity inside a blastula
the fluid-filled cavity inside a blastula
Blastocoel
(C)
Archenteron
Blastula
protostome and deuterostomes
two types of bilateral organisms development
body cavity forms within the space between the body wall and digestive cavity; mouth develops at blastopore; anus develops at opposite end; spiral cleavage
protostome development definition (body cavity, mouth, anus, cleavage)
nematodes, arthropods, annelids and mollusks
protostome phyla
body cavity forms as an outgrowth of digestive cavity; anus develops at blastopore; mouth develops at opposite end; radial cleavage
deuterostome development definition (body cavity, mouth, anus, cleavage)
echinoderms and chordates
deuterostome phyla
vertebrates and invertebrates
two categories of animals
with a backbone or vertebral column, not a formal taxonomic group
vertebrates definition
those lacking a backbone, not a formal taxonomic group
invertebrates definition
Cellular; lack of tissues and organs
Porifera level of organization
Absent
Porifera germ layers
Absent
Porifera symmetry
Absent
Porifera cephalization
Absent
Porifera body cavity
Absent
Porifera segmentation
Intracellular. tiny pores allow water to pass through. specialized cells extract oxygen and microorganisms
Porifera digestive system
Absent
Porifera circulatory system
Absent
Porifera respiratory system
Absent
Porifera excretory system (fluid regulation)
Absent
Porifera nervous system
Sexual; asexual (budding)
Porifera reproduction
Endoskeleton of spicules
Porifera support
Tissue; lack organs
Cnidaria level of organization
Two
Cnidaria germ layers
Radial
Cnidaria symmetry
Absent
Cnidaria cephalization
Absent
Cnidaria body cavity
Absent
Cnidaria segmentation
Gastrovasular cavity; some intracellular. single opening mouth = anus
Cnidaria digestive system
Absent
Cnidaria circulatory system
Absent
Cnidaria respiratory system
Absent
Cnidaria excretory system (fluid regulation)
Nerve net which branches through the body and ontrols the contractile tissues and feeding behavior
Cnidaria nervous system
Sexual; asexual (budding)
Cnidaria reproduction
Hydrostatic skeleton
Cnidaria support
Organ system
Platyhelminthes level of organization
Three
Platyhelminthes germ layers
Bilateral
Platyhelminthes symmetry
Present
Platyhelminthes cephalization
Absent
Platyhelminthes body cavity
Absent
Platyhelminthes segmentation
Gastrovascular cavity
Platyhelminthes digestive system
Absent
Platyhelminthes circulatory system
Absent
Platyhelminthes respiratory system
Canals with ciliated cells
Platyhelminthes excretory system (fluid regulation)
Head ganglia with longitudinal nerve cords
Platyhelminthes nervous system
Sexual (some hermaphroditic); asexual (body splits)
Platyhelminthes reproduction
Hydrostatic skeleton
Platyhelminthes support
Organ system
Annelida level of organization
Three
Annelida germ layers
Bilateral
Annelida symmetry
Present
Annelida cephalization
Coelom
Annelida body cavity
Present
Annelida segmentation
Separate mouth and anus
Annelida digestive system
Closed
Annelida circulatory system
Absent
Annelida respiratory system
Nephridia
Annelida excretory system (fluid regulation)
Head ganglia with paired ventral cords; ganglia in each segment
Annelida nervous system
Sexual (some hermaphroditic)
Annelida reproduction
Hydrostatic skeleton
Annelida support
Organ system
Mollusca level of organization
Three
Mollusca germ layers
Bilateral
Mollusca symmetry
Present
Mollusca cephalization
Coelom
Mollusca body cavity
Absent
Mollusca segmentation
Separate mouth and anus
Mollusca digestive system
Open
Mollusca circulatory system
Gills, lungs
Mollusca respiratory system
Nephridia
Mollusca excretory system (fluid regulation)
Well-developed brain in some cephalopods; several paired ganglia, most in the head; nerve network in the body wall
Mollusca nervous system
Sexual (some hermaphroditic)
Mollusca reproduction
Hydrostatic skeleton
Mollusca support
Organ system
Arthropoda level of organization
Three
Arthropoda germ layers
Bilateral
Arthropoda symmetry
Present
Arthropoda cephalization
Coelom
Arthropoda body cavity
Present
Arthropoda segmentation
Separate mouth and anus
Arthropoda digestive system
Open
Arthropoda circulatory system
Trachaea, gills or lungs
Arthropoda respiratory system
Excretory glands resembling nephridia
Arthropoda excretory system (fluid regulation)
Head ganglia with paired ventral cords; ganglia in segments, some fused
Arthropoda nervous system
Usually sexual
Arthropoda reproduction
Exoskeleton
Arthropoda support
Organ system
Nematoda level of organization
Three
Nematoda germ layers
Bilateral
Nematoda symmetry
Present
Nematoda cephalization
Pseudocoel
Nematoda body cavity
Absent
Nematoda segmentation
Separate mouth and anus
Nematoda digestive system
Absent
Nematoda circulatory system
Absent
Nematoda respiratory system
Excretory glands resembling nephridia
Nematoda excretory system (fluid regulation)
Head ganglia with dorsal and ventral nerve cords
Nematoda nervous system
Sexual (some hermaphroditic)
Nematoda reproduction
Hydrostatic skeleton
Nematoda support
Organ system
Echinodermata level of organization
Three
Echinodermata germ layers
Bilateral larvae, radial adults
Echinodermata symmetry
Absent
Echinodermata cephalization
Coelom
Echinodermata body cavity
Absent
Echinodermata segmentation
Separate mouth and anus
Echinodermata digestive system
Absent
Echinodermata circulatory system
Tube feet, skin gills
Echinodermata respiratory system
Absent
Echinodermata excretory system (fluid regulation)
Head ganglia absent; nerve ring and radial nerves; nerve network in the skin
Echinodermata nervous system
Sexual (some hermaphroditic); asexual by regeneration (rare)
Echinodermata reproduction
Endoskeleton of plates beneath outer skin
Echinodermata support
sponges
Phylum Porifera includes
Sea Jellies, Corals, Anemones
Phylum Cnidaria includes
Flatworms
Phylum Platyhelminthes Includes
Segmented Worms
Phylum Annelida includes
Clams, snails, Octopuses, Squid
Phylum Mollusca includes
Insects, Arachnids, Crustaceans
Phylum Arthropoda includes
Roundwroms
Phylum Nematoda includes
Sea Stars, Sea Urchins, Sea Cucumbers
Phylum Echinodermata includes
convergent or analogous based on physical appearance; gives false evolutionary relationships
Morphological similarities
similarities based on shared ancestry called homologous
molecular similarities
radial and asymmetry
non-bilaterians include (symmetry)
asymmetrical
sponges, asymmetrical, sessile, consume bacteria
phylum porifera (include, symmetry, movement, feeding)
eggs are in the sponge’s body and develop into larvae. water disperses larvae
porifera life cycle
A large opening on a sponge through which filtered water is expelled (1)
Osculum
tiny in-current pores that allow water to flow into sponge carrying with the the nutrients and oxygen that it needs for survival (2)
Ostia
a gelatinous region between the two layers of cells of a sponge
Mesohyl
Found in sponges, it is the central cavity into which water is drawn to filter nutrients lined with flagellated choanocytes (3)
Spongocoel
collar cells that use flagella to move a steady current of water through the sponge
Choanocyte
Found in sponges, these cells are mobile and perform numerous functions, including reproduction, transport of food particles to nonfeeding cells, and secretion of material that forms the spicules
Amoebocyte
Found in sponges, these consists of inorganic materials and support the animal; also provides a form of protection from other organisms
spicules
sessile
porifera movement
uses contractile tissues which act like muscles
cnidaria movement
two body plans: polyp and medusa
cnidaria morphology
The sessile, tubular form of a cnidarian with a mouth and tentacles at one end and a basal disk at the other
polyp form
The free-swimming, upside-down, bowl-shaped stage in the life cycle of the cnidarians; an example is the jellyfish
medusa
A specialized cell for which the phylum Cnidaria is named; consists of a capsule containing a fine coiled thread, which, when discharged, functions in defense and prey capture
cnidocytes
in cnidarians, the jellylike material located between the ectoderm and the endoderm
mesoglea
Stinging structure within each cnidocyte of a cnidarian that is used to poison or kill prey.
nematocyst
It is a hair-like trigger present in the cnidoblast which detects mechanical stimulation (eg: contact with prey).
cnidocil
comb jellies
Phylum Ctenophora include
via cilia
Ctenophora locomotion
stinging cells
Ctenophora specialized cells include
hermaphroditic
Ctenophora reproduction
