For dissection purposes, the anatomical directions of the body must be known: Anterior: toward the head or top – Also called cranial Posterior: opposite the head, toward the tail/anus – Also called Caudal Ventral: at the front of, in front Dorsal: behind, in the back of Lateral: away from the center of the body

Details of Phyla Fill in the defining characteristics into your chart – Specialization- are cells specialized for different jobs? – Symmetry- is it radial or bilateral? Is there symmetry at all? – Body Cavity- do they have a true coelom? Pseudocoelom? No body cavity at all? – Protostome/Deuterostome- does the blastopore become the mouth or the anus?

Details of Phyla Fill in the defining characteristics into your chart – Digestion- Do they digest inside the cells or outside the cells? How many openings does the digestive tract have? – Segmentation- are there divisions along the body specialized for different purposes? – Skeleton- internal, external, or hydrostatic? – Examples- what do animals in this phylum look like?

Skeleton- do you mean like bones? Skeleton refers to a support system- remember that animals do not have cell walls- so what holds animals into shape and prevents them from being a giant blob of cells? Hydrostatic skeleton- fluid pressing against muscles, no hard parts External skeleton- tough outer covering of chitin Internal skeleton- this is what YOU have- internal HARD substances like BONES

Phylum Porifera Cell Specialization: Yes (few) Symmetry: None (asymmetrical) Body Cavity: No Digestive Tract Protostome or Deuterostome: N/A

Phylum Porifera Digestion: Filter feeder Intracellular Segmentation: No Skeleton: Silica Example: Sponges

Phylum Porifera Respiration, Circulation, and Excretion: – occur via diffusion of gases and wastes between water and cells Reproduction: – asexual (budding) or sexual (internal fertilization) Response – Produce toxins to ward off predators (sea slugs)

Phylum Cnidaria Cell Specialization: Yes Symmetry: Radial Body Cavity: Gastro- vascular cavity (one opening) for feeding and gas exchange Protostome or Deuterostome: N/A

Phylum Cnidaria Digestion: Extracellular in the Gastrovascular cavity Segmentation: No Skeleton: Hydrostatic (two muscle layers and fluid) Examples: Jellyfish, coral, Portuguese man of war

Phylum Cnidaria Respiration, Circulation, and Excretion: –occur via diffusion of gases and wastes between water and cells, or cell to cell Reproduction: –Asexual (budding) or sexual (external fertilization) Response: –Nerve net –Stinging cells called cnidocytes on tentacles

Ctenophora Cell Specialization: Yes Symmetry: Radial Body Cavity: Gastro- vascular cavity with 2 openings: mouth and anal pore Protostome or Deuterostome: N/A

Ctenophora Digestion: Extracellular in the Gastrovascular cavity Segmentation: No Skeleton: Hydrostatic (two muscle layers and fluid) Examples: Jellyfish, coral, Portuguese man of war

Ctenophora Respiration, Circulation, and Excretion: – occur via diffusion of gases and wastes between water and cells Reproduction: – hermaphroditic Response: – Nerve net – No stinging cells, but have sticky cells called colloblasts used to capture prey – bioluminescent

Phylum Platyhelminthes Cell Specialization: Yes Symmetry: Bilateral Body Cavity: Acoelomate (have a digestive tract but no body cavity) Protostome or Deuterostome: Protostome

Phylum Platyhelminthes Digestion: Extracellular in the gastrovascular cavity one opening- mouth/anus Segmentation: No Skeleton: Hydrostatic Examples: Tapeworms, Flukes

Phylum Platyhelminthes Respiration, circulation and excretion: – Diffusion exchanges gas and excretes waste through body walls Response: – Ganglia in head region (groups of nerve cells) – Eyespots (detect light) Reproduction: – Sexual Hermaphrodites (produce both egg and sperm cells) Two worms can exchange sperm – Asexual fission

Rotifera Cell Specialization: Yes Symmetry: Bilateral Body Cavity: Pseudocoelomate (lined partially with mesoderm) Protostome or Deuterostome: Protostome Cilia covered corona

Rotifera Digestion: Extracellular Segmentation: No Skeleton: Hydrostatic Example: rotifers (seen in your pond water lab)

Rotifera Parthenogenetic reproduction (eggs are diploid) and only in certain conditions are males formed. Males are formed from unfertilized haploid eggs – Fertilize other haploid eggs and create a dormant fertilized egg that under the right conditions will become a parthenogenetic female.

Phylum Nematoda Cell Specialization: Yes Symmetry: Bilateral Body Cavity: Pseudocoelomate (lined partially with mesoderm) Protostome or Deuterostome: Protostome

Phylum Nematoda Digestion: Extracellular Segmentation: No Skeleton: Hydrostatic Example: Hookworms, Filarial worms, pinworms, heartworms

Phylum Nematoda Respiration, circulation and excretion: – Diffusion transports nutrients and gases – Flame cells remove excess water from the body Response: – Several ganglia in head region (groups of nerve cells) – Several nerve extend the length of the body Reproduction: – Sexual: separate sexes, internal fertilization

Phylum Annelida Cell Specialization: Yes Symmetry: Bilateral Body Cavity: Coelomate (lined with mesoderm) Protostome or Deuterostome: Protostome

Phylum Annelida Digestion: Extracellular Segmentation: Yes Skeleton: Hydrostatic Example: Leeches, earthworms, meal worms

Phylum Annelida Respiration, circulation and excretion: – Breathe using gills (aquatic) or use diffusion (terrestrial) – Closed circulatory system – Nephridia are specialized excretory organs that filter fluid Response: – Brain and several nerve cords – Sensory tentacles, chemical receptors Reproduction: – Sexual: separate sexes, external fertilization – Some annelids are hermaphrodites

Mollusca Cell Specialization: Yes Symmetry: Bilateral Body Cavity: Coelomate Protostome or Deuterostome: Protostome

Mollusca Digestion: Extracellular Segmentation: Yes Skeleton: Hydrostatic Examples: Snails, clams, squids, octopi

Phylum Mollusca Respiration, circulation and excretion: – Breathe using gills (aquatic) or use diffusion (terrestrial) – Open circulatory system – Nephridia are specialized excretory organs that filter fluid Response: – Simple nervous system (small ganglia, few nerve cords, simple sense organs) (ex: clams) – Well-developed brains (ex: octopi) Reproduction: – Sexual: external or internal fertilization Hermaphrodites or separate sexes

Phylum Arthropoda Cell Specialization: Yes Symmetry: Bilateral Body Cavity: Coelomate Protostome or Deuterostome: Protostome

Phylum Arthropoda Digestion: Extracellular Segmentation: Yes Skeleton: Exoskeleton Examples: Crustaceans, Arachnids, Insects

Phylum Arthropoda Respiration, circulation and excretion: – Trachael tubes or book lungs – Open circulatory system – Malphigian tubules extract waste from the blood and add it to digestive waste Response: – Several ganglia in head region (groups of nerve cells) – Several nerve extend the length of the body Reproduction: – Sexual: separate sexes, internal fertilization

Phylum Echinodermata Cell Specialization: Yes Symmetry: Radial Body Cavity: Coelomate Protostome or Deuterostome: Deuterostome

Phylum Echinodermata Digestion: Extracellular Segmentation: Yes Skeleton: Endoskeleton Examples: Sea stars, Brittle stars, sand dollars

Phylum Echinodermata Respiration, circulation and excretion: – Diffusion through tube feet – Circulation through water vascular system Response: – Nerve ring that surrounds the mouth has radial nerves that connect to body sections Reproduction: – Sexual: separate sexes, external fertilization

Phylum Chordata Cell Specialization: Yes Symmetry: Bilateral Body Cavity: Coelomate Protostome or Deuterostome: Deuterostome Digestion: Extracellular Segmentation: Yes Skeleton: Endoskeleton Example: Lancelet, sea squirts

Nonvertebrate chordates Cell Specialization: Yes Symmetry: Bilateral Body Cavity: Coelomate Protostome or Deuterostome: Deuterostome

Nonvertebrate Chordata Digestion: Extracellular Segmentation: Yes Skeleton: Endoskeleton Example: Lancelet, sea squirts