Protostomes (Lab 7)

What are the three types of body symmetry in Animalia?

Asymmetrical

Radial

Bilateral

What is the difference between diploblastic and triploblastic body development?

Mesoderm

• 3 vs 2 germ layers

Ectoderm

BECOMES skin & nervous system

Endoderm

BECOMES gut

Mesoderm

BECOMES skeleton

What are the three types of body cavities found in triploblastic animals?

Acoelomate, Psuedocoelomate, and Coelomate

Coelom

a fluid-filled space that separates the gut and internal organs from the rest of the body

Protostome Embryonic Development

Determinate Cell Fate
Schizocoelous
Blastopore → Mouth

Deuterostomes Embryonic Development

Indeterminate Cell Fate
Enterocoelous
Blastopore → Anus

Schizocoelous

body cavity forms when the mesodermal tissue "splits"

Enterocoelous

The body cavity forms when pockets of the primitive gut (archenteron) bud off

What are the two superphyla of protostomes?

Ecdysozoa & Lophotrochozoa

Which phyla are part of Ecdysozoa?

Arthropoda

Which pyla are part of Lophotrochozoa?

Mollusca

What is a key trait of members of Ecdysozoa?

Ecdysis - shed their outer body covering

Phylum Nematodan Characteristics

Roundworms

• Pseudocoelom
• Complete Digestive Tract
• Tough Cuticle
• Longitundinal Muscles Only

What species are part of phylum nematoda?

Vinegar Eels

Phylum Arthropoda Characteristics

• Jointed Appendages
• Segmented Bodies
• Chitin Exoskeleton
• Open Circulatory System
• Ventral Nerve Chord
• Cephalized Ganglia

What species are part of phylum Arthropoda?

Hermit Crab

What subphylum are Centipede and Millipede part of?

Myriapoda

Characteristics of Centipedes

• Carnivorous
• 1 Pair of Legs Per Segment
• Poisonous Fangs

Characteristics of Millipedes

• Herbivores
• 2 Pairs of Legs Per Segment

Characteristics of Spiders (Subphylum - Chelicerara)

• Chelicerae (fangs)
• Pedipalps (accessory appendages by the mouth)
• Breathe using book lungs

What two subphylum within Arthropoda are the most closely related?

Hexapoda and Crustacea

What are the synapomorphies between Hexapoda and Crustacea?

Heavily Segmented (Head, Thorax, Andomen)

Lophophore

a crown of ciliated tentacles that function in feeding

Trochophore

Ciliated larval stage of annelids and mollisca

Phylum Platyhelminthes Characteristics

Flatworms

• Flat bodies
• Acoelomate
• Ladder-like nervous system
• IMCOMPLETE digestive tract
• NO circulatory system

What species are apart of phylum platyhelimthes?

Planarians and Tapeworms

What are some key traits of Planarians?

• Scavengers
• Protonephridia (& flame bulbs)
• Eyespots (ocelli)

What are some key traits of Tapeworms?

• Parasites
• NO digestive system
• Scolex
• Proglottids (repoductive segments)

Phylum Brachiopoda Charcteristics

• Complete Gut
• CLOSED Circulatory System
• Protected between two hinged valves (shells)
• Shells of CaCO3

Phylum Mollusca Charcteristics

• Complete Gut
• OPEN Circulatory System
• Radula
• Foot
• Mantle
• Visceral Mass

What species are within phylum mollusca?

Snail

Radula

scrapes food

Foot

movement and food capture

Mantle

Secretes Shell

Vesceral Mass

Contains organs

What are some key traits of squid?

• Predators
• CLOSED Circulatory System w/ 3 hearts (dual circuit circulation)
• Chromatophores
• 8 arms PLUS 2 longer tentacles
  Pen

Which subphylum is considered the most advanced invertebrates?

Cephalopods b/c

• Intelligence
• Well-Developed Eyes
• and etc.

Chromatophores

pigmented cells that help these animals change color

• (communication & camouflage)

Pen

remanant of shell

Phylum Annelida

• Truly segmented body cavity (septa)
• CLOSED cirulatory system
• LOST spiral cleavage

What species are apart of phylum annelida?

Earthworm

What are key traits of earthworms & lecches (Class Sedentaria)?

• Few to NO setae (bristles)
• Clitellum

Clitellum

Glues them together while mating

Anatomy of Squid

Anatomy of Crawfish

Anatomy of Earthworm