BIOLOGY 111 invertebrates

Porifera symmetry

Asymmetrical

Porifera tissue layers

No true tissues (cell-level organization)

Porifera feeding method

Filter feeding using choanocytes

Choanocyte function

Create water flow and capture food

Amoebocyte function

Digestion nutrient distribution and spicule formation

Spicule function

Structural support and defense

Spicule material

Calcium carbonate or silica

Spongin

Flexible protein fiber in sponges

Sponge reproduction

Both sexual and asexual

Sponge larva

Free-swimming

Sponge adult body plan

Sessile

Spongocoel

Central internal cavity

Ostia

Pores allowing water to enter sponge

Osculum

Opening where water exits

Porifera synapomorphy

Choanocytes

Ecological role of sponges

Filter water habitat formation

Sponge skeleton

Made of spicules and spongin

Why sponges lack symmetry

No tissue layers to organize structure

Do sponges have a nervous system

No

Cnidarian symmetry

Radial symmetry

Cnidarian germ layers

Diploblastic

Cnidarian digestive system

Gastrovascular cavity one opening

Medusa form

Free-swimming sexual reproduction

Polyp form

Sessile asexual budding

Cnidocyte

Specialized stinging cell

Nematocyst function

Prey capture defense

Hydrostatic skeleton

Fluid pressure provides support

Cnidarian nervous system

Nerve net

Cnidarian clades

Hydrozoa Scyphozoa Cubozoa Anthozoa

Coral symbiosis

Zooxanthellae algae photosynthetic

Cause of coral bleaching

Loss of zooxanthellae due to stress

Anthozans include

Sea anemones and corals

Box jellies rank

Most venomous cnidarians

Jellyfish life cycle

Alternates medusa and polyp (except Anthozoa)

Ctenophore symmetry

Biradial symmetry

Ctenophore locomotion

Ctenes (fused cilia rows)

Colloblast function

Sticky cells trap prey

Do ctenophores have cnidocytes

No

Ctenophore digestive system

Complete two openings

Ctenophore nervous system

More advanced than cnidarians

Bilateria symmetry

Bilateral

Bilateria germ layers

Triploblastic

Cephalization

Sensory structures concentrated at head

Protostome cleavage

Spiral determinate

Deuterostome cleavage

Radial indeterminate

Protostome blastopore

Mouth

Deuterostome blastopore

Anus

Coelom function

Allows organs to develop cushions organs

Platyhelminth body cavity

Acoelomate

Platyhelminth digestive system

Incomplete GVC

Platyhelminth nervous system

Ladder-like nerve cords

Planarian reproduction

Regeneration

Turbellaria

Free-living flatworms

Cestoda

Tapeworms endoparasites

Trematoda

Flukes parasitic

Tapeworm nutrient absorption

Across body wall no digestive tract

Parasitic adaptations

Reduced organs high reproduction

Flame cells

Excretory osmoregulation cells

Major platyhelminth synapomorphy

Flattened body increases SA

Rotifer body cavity

Pseudocoelomate

Corona function

Ciliated feeding crown

Rotifer reproduction

Parthenogenesis common

Rotifer digestive tract

Complete

Rotifer habitat

Freshwater

Annelid body cavity

Coelomate

Segmentation advantage

Specialization efficient locomotion

Annelid synapomorphy

Segmented body

Chaetae/setae

Chitin bristles for movement

Polychaeta

Marine worms parapodia

Oligochaeta

Earthworms

Hirudinea

Leeches

Earthworm digestive system

Complete tract crop gizzard

Metanephridia function

Excretion osmoregulation

Annelid circulatory system

Closed

Earthworm reproduction

Hermaphroditic

Parapodia function

Locomotion respiration

Mollusc body plan

Foot mantle visceral mass

Mantle function

Secretes shell

Radula

Rasping feeding organ

Open circulatory system

Most molluscs

Closed circulatory system

Cephalopods

Gastropods

Snails slugs

Bivalves

Clams oysters mussels filter feeders

Cephalopods

Octopuses squid cuttlefish

Cephalopod intelligence

Most advanced invertebrate brains

Cephalopod defense

Camouflage ink jet propulsion

Mollusc larva

Trochophore

Shell reduction occurs in

Cephalopods and slugs

Nematode body cavity

Pseudocoelomate

Cuticle

Protective layer molted for growth

Ecdysozoa synapomorphy

Molting (ecdysis)

Nematode digestive system

Complete gut

C. elegans significance

Genetics model organism

Nematode movement

Thrashing due to longitudinal muscles

Roundworm reproduction

Sexual internal fertilization

Arthropod synapomorphy

Chitin exoskeleton

Exoskeleton advantage

Protection muscle anchoring

Exoskeleton disadvantage

Vulnerable during molting

Tagmosis

Fusion of segments into functional units

Arthropod circulatory system

Open hemolymph