Chapter 28 Basu Bio112

Invertebrates

Animals that lack backbone

What percentage of known animals species are invertebrates

95%

Name the basal phylums

Porifera

Cnidaria

Name the invertebrate phylums

Porifera

Cnideria

Platyhelminthes

syndermata

lophophorates: Ectoprocta & Brachiopoda

Mollusca

Annaleds

Nematoda

arthropoda

echinodermata

chordata

porifera habitat and lifestyle

aquatic, marine

Porifera features

no true tissue

no cephalization

no organ systems

filter feeders

sessile as adults

Porifera anatomy

osculum: large openings where water is expelled

Ostia: pores where water enters through

Spongocoel: large central cavity

Mesohyl: jelly that contains collagenous fibers

Mesohyl parts

choanocyte: generates and filters

amoebocyte: delivery

Pinacocyte: forms, phagocytize

Spongin: fibers

Spicules: support

Porifera reproduction

Asexual = fragmentation or budding

Sexual: Hermaphroditic (M or F at different times)

Porifera examples

sponges

clathrina clathrus

staurocalyptus

Acarnus erithacus

Cnidaria examples

jellyfish

hydra

sea anemones

coral

Cnidaria features

radial symmetry

no cephalization

sessile polyp and drifting medusa

carnivores

simple nervous system

diploblastic

dimporhpic

Cnidaria habitat

aquatic

Cnidaria anatomy

sac like body

gastrovascular cavity: 1 opening to digestive sac

mesoglea

hydrostatic skeleton

CNIDOCYTE: stinging cell

NEMATOCYTES: cnidocyte organelle with barbed base and long coil

Protostome superphylums

lophotrochozoan & Ecdysozoa

cephalization

: concentration of nervous tissue and sensory organs in head

Superphylum Lophotrochozoa phylums

syndermata (rotifers)

platyhelminthes

mollusca

brachiopods and ectoprocts

annelids

ecdysozoa

nematoda

arthropoda

synermata (rotifers) habitat

aquatic

synermata (rotifers) features

pseudocoelum

microscopic, cylindrical body

free living

synermata (rotifers) reproduction

asexual: parthogenesis

synermata (rotifers) anatomy

corona

jaws

stomach

alimentary canal

Platyhelminthes example

flukes

tapeworms

planarians

flatworms

Platyhelminthes habitat

marine, freshwater & damp terrestrial places

Platyhelminthes lifestyle

acoelomates and parasites; free living

Platyhelminthes features

flat shape

diffusion across surface

nervous system and excretory system

no lophophore or trochophore larvae

triploblastic

Platyhelminthes anatomy

gastrovascular cavity

nervous system: ganglia, ventral nerve chord, eye spots

excretory system: protonephridia w/ flame cells

O2 / CO2 exchange at cell level

Platyhelminthes reproduction

monoecious (male and female; internal fertilization)

Asexual= Fission

tapeworms life cycle

1. Introduction: eggs in feces

2. Contamination: livestock eats contaminated vegetation

3. Penetration: embryos penetrate intestine wall

4. Development: embryos develop into larvae

5. Ingestion: humans eat livestock

6. Scolex Attachment to Intestine

7. Proglottids Form

Mollusca clades

Polyplacophora

Gastropoda

Bivalvia

Cephalopoda

Mollusca examples

chitons

snails and slugs

clams and oysters

squids and octopi

Mollusca habitat

marine, some freshwater

some snails and slugs are terrestrial

Mollusca features:

calcium carbonate shell

true coelom

triploblastic

cephalization ( not in bivalves)

digestive, respiratory, circulatory system

Mollusca anatomy

muscular foot, visceral mass, mantle

radula

gills

open circulatory system

Mollusca reproduction

separate sexes

trochophore larvae stage

Brachiopods and Ectoprocts feature

lophophore: crown of ciliated tentacles around mouth used for feeding

Brachiopods and Ectoprocts examples

ectoprocts: creeping bryozoan

brachiopod: lampshell

Annelida clades

Errantia and Sedentaria

Annelida examples

feather duster, tubeworm, earthworms, leeches

Annelida features

segmentation

well developed organ system

soft body

Errantia features and anatomy

marine

multiple parapodia

cirri = sensory organs

Earthworm features and anatomy

- few bristles

- no parapodia

- deposit feeders

- terrestrial or freshwater

leeches features and anatomy

- no bristles

- no parapodia

- freshwater or terrestrial

- anticoagulant

superphylum ecdysozoa examples

crayfish, lobsters, crabs, barnacles, spiders, ticks, insects

superphylum ecdysozoa common characteristics

cuticle

ecdysis process

superphylum ecdysozoa phylum

nematodes and arthropods

nematoda examples

roundworms

trichinella spidalis = trichinosis

wuchereria bancroft = causes eledantiasis

coenorhabiotis elegans = important research animals

microscopic filial worm = carried by mosquitos

nematoda anatomy

no segmentation

pseudocoelom

exoskeleton = rough cuticle

Phylum arthropoda characteristics

specialized body segments (2-3) = head thorax abdomen

hard exoskeleton

jointed appendages

Phylum arthropoda anatomy

cuticle = support, protection, attachment

open circulatory system = hemolymph

gas exchange = gills or trachea and book lungs

ecdysis = exoskeleton shed/molt

Phylum arthropoda clades

Chelicerates

myriapod

crustaceans

insects

class chelicerates examples

arachnids= spiders, scorpions, ticks, mites

class chelicerates lifestyle

land predators or parasites

class chelicerates features and anatomy

chelicerae = claw appendages; fangs in spiders

pedipalps = feeding appendage

cephalothorax = upper body

abdomen = lower body

no anntenae

class myriapod examples

centipede and millipede

class myriapod features and anatomy

many identical segments and legs

chewing mandibles = feeding

1 pair of anntenae

class myriapod lifestyle

terrestrial

millipede characteristics

detritivores/herbivores

2 pairs of legs per segment

round shape

centipede characteristics

predators

1 pair of leg per segment

poison claw

flat shape

Crustacean example

lobsters, shrimp, crayfish, krill, barnacles, dophnia "water flea"

Crustacean lifestyle

mostly marine and freshwater; some land

predators , herbivores, scavengers, filter feeders, some parasites

Crustacean anatomy

2 pair of antennae

chewing mandibles

many legs

insects features

6 legs

3 segments

2 pairs of wings

1 pair of antennae

compound eyes

insects anatomy

3 body parts

1. head: 1 pair of antennae and compound eye

2. thorax: 3 pairs of legs and 2(0-2) pairs of wings

3. Abdomen: complex and organ system

- Malpighian tubule = excretion of metabolic waste

- tracheal system = gas exchange

insect lifestyle

complex social systems

insects impact

pollination

food for wildlife

damage to homes

disease vectors

crop destruction

parasites

research

Deuterostomes phylum

Echinodermata and Chordata

Echinodermata examples

sea stars, sea urchins, sand dollars, sea biscuit

Echinodermata lifestyle

free living and marine

predators and herbivores

Echinodermata features and anatomy

endoskeleton

large coelom

water vascular system = tube feet

porifera summary

examples: sponges

descriptions:

lack tissue

choanocytes

collar cells

cnidaria summary

examples: hydra, jellies, sea anemones, corals

descriptions:

- nematocytes & cnidocytes

- radial symmetry

- diploblastic

- gastrovascular cavity

Platyhelminthes summary

examples: flatworms

descriptions:

- flat coelomates

- gastrovascular cavity w/ no digestive tract

syndermata summary

examples: rotifers

descriptions:

- pseudocoelomates

- alimentary canal = mouth and anus

- jaws

lophophorate summary

examples: Ectoprocta and brachiopods

descriptions:

- coelomates w/ lophophores

mollusca summary

examples: clams. snails, squids

descriptions:

- coelomates

- muscular foot, visceral mass, mantle, shell

annelida summary

examples: segmented worms

descriptions:

- coelomates

- segmented wall and internal organs

nematoda summary

examples: roundworms

descriptions:

- cylindrical

- pseudocoelomates

- tapered ends

- no circulatory system

- ecdysis

arthropoda summary

examples: spiders, centipedes, crustaceans, insects

descriptions:

- coelomates

- segmented body

- jointed appendages

- exoskeleton= protein and chitin

Echinodermata summary

examples: sea stars and sea urchins

descriptions:

- coelomates

- water vascular system

- endoskeleton

- symmetrical larvae

- 5 part body organization

Chordata summary

examples: lancelets, tunicates, vertebrates

descriptions:

- coelomates

- notochord

- dorsal hollow nerve cord

- pharyngeal slits

- post anal tail