Transcript You`re Such an Animal!

You’re Such an Animal!
What is an animal?
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Multicellular heterotrophs – take in food,
digest it, distribute nutrients to cells
Eukaryotes, cells lack cell walls
Maintain homeostasis
Divided into 2 groups: invertebrates and
chordates
Characteristics
of Animals
What is an invertebrate?
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No backbone
Have special parts for locomotion
Some are sessile (permanently attached or
fixed; not free moving)
Some reproduce by budding, some with
sperm and egg, some by parthenogenesis
(unfertilized egg becomes an individual)
some invertebrates can regenerate lost
parts or even a complete individual from a
broken piece.
Porifera – Sponges!
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Simplest animals
Sac-like bodies – hole in the top leading to
open body cavity
Filter feeders - water flows out through
top hole and in through pores in body wall.
No tissues, different cells perform different
functions
Both sexual and asexual, motile larvae
Porifera - sponges
The two pictures on left show living sponges, the two
pictures on right show the skeletons – used commercially.
http://www.middleschoolscience.com/sponges.htm
http://www.ucmp.berkeley.edu/porifera/porifera.html
http://www.teaching-biomed.man.ac.uk/bs1999/bs146/biodiversity/porifera.htm
Sponges
Phylum
Porifera
Cnidaria
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Radial symmetry
Hollow gut with a single opening
Tentacles with stingers
Prey is stung and stuffed through opening in the
gut.
Gets oxygen, water, and gets rid of waste
through diffusion
Cnidarians -
Sea anemones, coral, jellyfish
http://en.wikipedia.org/wiki/Image:Giant_Green_Anemone.gif
http://www.ucmp.berkeley.edu/cnidaria/fungiid.html
Jellyfish
Hydra
Coral
Sea anemones
Sea anemone movement
Between two
cells layers the
sea anemone
has a jellylike
layer with
nerve cells and
contractile
fibers –
this is how it
moves.
Stinging
Animals
http://www.bionat.unipi.it/deee/idx_arch_img.html
Platyhelminthes (flat worms)
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Bilateral symmetry
Most are parasites
Flukes feed on host tissue
Tapeworms feed on materials in the host’s
gut.
Planarians
Tapeworms
Flukes
Nematoda (round worms)
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Most are microscopic
Most hunt for their food
Complete digestive system – two openings
50 species are parasites
transmitted in untreated sewage
live everywhere
Move by long muscles
Sexual reproduction, sperm are amoeboid
Nematoda
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Roundworms
Guinea worm
Ascaris (intestinal worms)
Necator (hookworm)
Annelida (segmented worms)
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Segmented bodies help in crawling and
burrowing into dirt and holes
Earthworms are hermaphrodites
Most are filter feeders, carnivores or
parasites (ex: Leeches feed on animal’s
blood)
Over 12,000 known species of earthworms,
leeches, and clamworms
Earthworms and Leeches
Annelida
Ocean tubeworms
Earthworm – note segments (2) and
Clitellum (1)
http://animaldiversity.ummz.umich.edu/site/resources/jeffrey_jeffords/misc.inverts/tubes.jpg/view.html
Annelida
Diagram of
earthworm anatomynote development
of organs.
Annelida
This shows a worm’s
five pairs of beating
hearts
Phylum
of Worms
Mollusca
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Bilateral symmetry
Unsegmented, usually have a defined
head
Main parts include: a muscular foot, a
head, and a visceral mass (contains
organs)
Live in oceans, freshwater, and on land
Snails
Mollusca
http://www.medslugs.de/E/Med/Phyllidia_flava_10.htm
http://www.medslugs.de/E/Med/Flabellina_pedata_28.htm
Clams
Mollusca
http://home.planet.nl/~erikveldhuis/index.html
Cone Shell
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400 to 500 species of cone shell mollusks
harmful to humans - deadly nerve poisons
Hunt prey with a muscular, retractable proboscis that has a
mouth, a salivary gland, and teeth.
Chambered Nautilus
The Chambered
Nautilus is a “living
fossil” – a member
of the cephalopods
which includes
octopus and squid.
Close relatives date
back 100’s of
millions of years.
It propels itself
close to the sea
floor by shooting
water from its
movable siphon.
Picture taken by Judy Jones
Squid & Octopus
Phylum Mollusca