• Pseudocoel
• cuticle
• dioecious
• complete digestive tract
• FW, marine, damp soil, parasites of plants and animals
• Roundworms

• Largest phylum, 1 million
• segmented
• jointed legs
• Exoskeleton
• Blood vascular system (hemocoel, hemolymph)
• reduced coelom
• brain and ventral nerve cord

Excretory system: metanephridia, Malpighian tubules (terrestrial species)

Gas Exchange: Gills, Body wall, Book lungs, trachae (terrestrial species)

Reproduction: primarily dioecious, pathenogenesis

horseshoe crabs, spiders, scorpians, mites

• Cephalothorax and abdomen
• Chelicerae (fang like appendages in mouth)
• carnevorous or parasites

Class Arachnids: spiders, mites, scorpians, ticks

4 pairs of legs

Millipedes: 2 pairs of legs/ segment

Centipede: 1 pair of legs/ segment

Class insecta: largest anthropod group, Diverse

Body division: head, thorax, abdomen

6 legs

Adaptations to terrestrial environment:

• waxy layer of cuticle
• Malpighian tubules

Flight evolved

Two pairs of wings

Hexapoda Continuation

Feeding:

• Herbivores
  • pollinators (bees, wasps, butterflies), feed on nectar
  • crop pests
• carnivorous, parasites
• disease vectors, e.g. mosquitoes

Development:

• Incomplete metamorphosis
  • egg, nymph, adult
• Complete metamorphosis
  • egg, larvae, pupa, adult

Lobster, Shrimp, crabs

• Freshwater, marine, terrestrial
• two pairs of antennae
• gills
• filter feeders, carnivore

Deutrostomia

Anus forms near or at site of blastomere

• Chordata
• Echinodermata

starfishes, feather stars, sea urchins, sea cucumbers

-entirely marine

-adults, 5 parts (pentaradial, pentamerous) radial symmetry

-endoskeleton containing calcereous spines and plates

• Water vascular system
• tube feet their functions
• Blood vascular system- nutrients and waste transport
• Excretory system-
• Larval symmetry- bilateral

1.) Notochord- endoskeleton

2.) Dorsal Hollow Nerve Cord

3.) Pharyngeal gills

4.) Postanal tail

Tunicates- because have a body cavity(called tunicates) that contains high percentage of cellulose, entirely marine

Solitary and colonial

Filter feeders

• pharynx where food is concentrated- moves through pharynx

Gas exchange

• At gills

BVS

Cranium- skull encasing brain

Neural crest cells- bone and cartilage of skull, teeth, nerves, inner skin of face

Myxini= hagfishes

Marine

Notochord; no vertebrae

Jawless, scavengers (dead and dying fish)

Produce slime

• Lampreys marine and FW
• Vertibrae, Notochord
• Parasitic and non parasitic species; Larvae
• Jawless
• Latch onto fish and suck the blood out
• Larvae look like cephalochordates

• Jaws
• mineralized skeleton
• paired appendages
• Jaws arose from gill arches

• Sharks and rays
• Cartilaginous fish (skeleton of cartilage)

Osteichthyans

• Lungs or lung derivative
• Rayfinned fish
• bony skeleton- calcified
• swim bladder- lung derivative
  • By adjusting amount of gas in bladder; density, thus bouyancy regulated
  • Significance- saves a lot of energy, conserves energy as some fish always have to be swimming

• Four limbed with feet
• originated from lobe finned ancestors
• Movement from water to land= stable aquatic environment to harsh terrestrial environment

• First land vertebraes
• earliest diverging tetrapods
• shell less eggs, suseptible to dehydration
• gas exchange across skin and surface of lungs

Amniotes= amniota

• Amniotic egg- adaptation allowing development on land
• made diversification of terrestrial vertabraes possible

Egg Characteristics

• Shell
  • prevents desiccation
  • allows gas exchange
• Extraembryonic membranes
  • amnion- fluid filled sac.
  • aqueous environment for embryonic development
• Allantois- gas exchange/ waste storage
• chorion- gas exchange
• Yolk sac

• Turtles, snakes, lizards, alligators, crocodiles, dinosaurs,
• Epidermal scales containing keratin
• prevents desiccation
• most egg layers

• Descended from theropods dinosaur lineage
• no teeth

Adaptation to flight

• wings
• feathers-epidermal derivative
• pneumatized bone < weight