You’re Such an Animal!You’re Such an Animal!

What is an animal?What is an animal? Multicellular heterotrophs – take in Multicellular heterotrophs – take in

food, digest it, distribute nutrients to food, digest it, distribute nutrients to cellscells

Eukaryotes, cells lack cell wallsEukaryotes, cells lack cell walls Maintain homeostasisMaintain homeostasis Divided into 2 groups: invertebrates Divided into 2 groups: invertebrates

and chordatesand chordatesCharacteristics

of Animals

What is an invertebrate?What is an invertebrate? No backboneNo backbone Have special parts for locomotionHave special parts for locomotion Some are Some are sessile sessile (permanently attached or (permanently attached or

fixed; not free moving)fixed; not free moving) Some reproduce by budding, some with Some reproduce by budding, some with

sperm and egg, some by sperm and egg, some by parthenogenesisparthenogenesis (unfertilized egg becomes an individual)(unfertilized egg becomes an individual)

some invertebrates can some invertebrates can regenerateregenerate lost lost parts or even a complete individual from a parts or even a complete individual from a broken piece.broken piece.

Porifera – Sponges!Porifera – Sponges! Simplest animalsSimplest animals Sac-like bodies – hole in the top leading Sac-like bodies – hole in the top leading

to open body cavityto open body cavity Filter feeders - water flows out through Filter feeders - water flows out through

top hole and in through pores in body top hole and in through pores in body wall. wall.

No tissues, different cells perform No tissues, different cells perform different functionsdifferent functions

Both sexual and asexual, motile larvaeBoth sexual and asexual, motile larvae

Porifera - spongesPorifera - spongesThe two pictures on left show living sponges, the twopictures on right show the skeletons – used commercially.

http://www.ucmp.berkeley.edu/porifera/porifera.html

http://www.teaching-biomed.man.ac.uk/bs1999/bs146/biodiversity/porifera.htm

http://www.middleschoolscience.com/sponges.htm

Sponges

Phylum Porifera

CnidariaCnidaria Radial symmetryRadial symmetry

Hollow gut with a single openingHollow gut with a single opening Tentacles with stingersTentacles with stingers Prey is stung and stuffed through opening Prey is stung and stuffed through opening

in the gut. in the gut. Gets oxygen, water, and gets rid of waste Gets oxygen, water, and gets rid of waste

through diffusionthrough diffusion

Cnidarians - Cnidarians - Sea anemones, coral, Sea anemones, coral, jellyfishjellyfish

http://www.ucmp.berkeley.edu/cnidaria/fungiid.html

http://en.wikipedia.org/wiki/Image:Giant_Green_Anemone.gif

Jellyfish Hydra

Coral

Sea anemones

Sea anemone movementSea anemone movementBetween two cells layers the sea anemone has a jellylike layer withnerve cells and contractile fibers –this is how it moves.

http://www.bionat.unipi.it/deee/idx_arch_img.html

Stinging Animals

Bilateral symmetryBilateral symmetry

Most are parasitesMost are parasites Flukes feed on host tissueFlukes feed on host tissue Tapeworms feed on materials in the Tapeworms feed on materials in the

host’s gut. host’s gut.

Platyhelminthes (flat Platyhelminthes (flat worms)worms)

Planarians

Tapeworms

FlukeFlukess

Nematoda (round worms)Nematoda (round worms) Most are microscopicMost are microscopic Most hunt for their foodMost hunt for their food Complete digestive system – two Complete digestive system – two

openingsopenings 50 species are parasites50 species are parasites transmitted in untreated sewagetransmitted in untreated sewage live everywhere live everywhere Move by long musclesMove by long muscles Sexual reproduction, sperm are Sexual reproduction, sperm are

amoeboidamoeboid

NematodaNematoda RoundwormsRoundworms

Guinea worm

Ascaris (intestinal Ascaris (intestinal worms)worms)

Necator (hookworm)Necator (hookworm)

Annelida (segmented Annelida (segmented worms)worms)

Segmented bodies help in crawling Segmented bodies help in crawling and burrowing into dirt and holesand burrowing into dirt and holes

Earthworms are hermaphroditesEarthworms are hermaphrodites Most are filter feeders, carnivores or Most are filter feeders, carnivores or

parasites (ex: Leeches feed on parasites (ex: Leeches feed on animal’s blood) animal’s blood)

Over 12,000 known species of Over 12,000 known species of earthworms, leeches, and earthworms, leeches, and clamwormsclamworms

Earthworms and LeechesEarthworms and Leeches

AnnelidaAnnelida

Ocean tubeworms Earthworm – note segments (2) andClitellum (1)

http://animaldiversity.ummz.umich.edu/site/resources/jeffrey_jeffords/misc.inverts/tubes.jpg/view.html

AnnelidaAnnelida

Diagram of Diagram of

earthworm earthworm anatomy-anatomy-

note developmentnote development

of organs.of organs.

AnnelidaAnnelida

This shows a worm’s five pairs of beatinghearts

Phylum of Worms

MolluscaMollusca

Bilateral symmetryBilateral symmetry Unsegmented, usually have a defined Unsegmented, usually have a defined

headhead Main parts include: a muscular foot, a Main parts include: a muscular foot, a

head, and a visceral mass (contains head, and a visceral mass (contains organs)organs)

Live in oceans, freshwater, and on Live in oceans, freshwater, and on land land

SnailsSnails

MolluscaMollusca

http://www.medslugs.de/E/Med/Flabellina_pedata_28.htm

http://www.medslugs.de/E/Med/Phyllidia_flava_10.htm

ClamsClams

MolluscaMollusca

http://home.planet.nl/~erikveldhuis/index.html

Cone ShellCone Shell 400 to 500 species of cone shell mollusks 400 to 500 species of cone shell mollusks harmful to humans - deadly nerve poisonsharmful to humans - deadly nerve poisons Hunt prey with a muscular, retractable proboscis Hunt prey with a muscular, retractable proboscis

that has a mouth, a salivary gland, and teeth. that has a mouth, a salivary gland, and teeth.

Chambered NautilusChambered Nautilus

The ChamberedNautilus is a “livingfossil” – a memberof the cephalopodswhich includes octopus and squid. Close relatives date back 100’s of millions of years. It propels itself close to the sea floor by shootingwater from its movable siphon.

Picture taken by Judy Jones

Squid & OctopusSquid & Octopus

Phylum Mollusca