3.4 Animal Kingdom ( Invertebrates )

Whats the main characteristic of classifying animals ?

• Is to classify if the animals has a presence of a backbone -

• With a backbone they are vertebrates

• Without a backbone they are invertebrates

Describe the level or organization in the human body

• Atom

• Molecule

• Macromolecule

• Organelle

• Cell

• Tissue

• Organ

• Organ System

• Then final the Organism ( Human )

Describe and identify the number of body layers

• Ectoderm - outer layer ( skin, nerves, sense organs)

• Mesoderm - Middle layer ( muscles, blood, kidneys, and reproductive organs )

• Endoderm - Inner layer (other internal organs)

What are body cavities? (coelom)

• Some animals have a digestive tract and other organs suspend fluid filled cavity called coelom

• Coelom allows for a faster movement and responses to complex organ systems

What is Segmentation?

• A division of body into repetitive sections of worms and scorpions

• Segments can move independently allowing for complex locomotion

Reproduction of segmentation

• Most reproduce sexually ( haploid gametes fuse into a diploid organism )

• Fertilization can occur externally or internally

Invertebrate Animals are ?

• Animals without a backbone

• Sponges, cnidarians, worms, molluscs, echinoderms, and arthropods.

What are sponges?

• Found in salt or freshwater

• Only 2 layers of cells and no tissue

• Cells are so independent that if you were to separate them they would reassemble into a complete sponge

• Feed by trapping food particles in water that pass through their bodies.

What are Cnidarians

• Jelly fish, coral, Sea Anemones

• only 2 layers of cells

• swim to catch prey using tentacles around mouth

• food digested in gastrovascular cavity

• 2 basic body forms

What are cnidarians two body forms?

• First is Polyp - cylindrical form that attaches to a surface and extends tentacles upward and outward

• Second is Medusa - flattened mouth down form that is unattached

What are Flatworms - Phylum Platyhelminthes

• they have 3 layers of cells

• Includes - parasitic tapeworms, flukes, and free living planarians

Segmented worms - phylum annelida

• distinct head and several organ systems including nervous digestive and circulatory

What are the molluscs Classes ?

• Class Bivalvia - includes clams, muscles, oysters, and scallops

• Class gastropoda- includes shelled snails and no shelled slugs

• Class Cephalopoda - includes octopuses and squids

What is arthropods ? (phylum Arthropoda)

• Includes spiders, scorpions, crustaceans, and insects

• Segmented bodies made up of hard exoskeleton made of protein and chitin

• Exoskeleton provides rigid protection, muscle attachement points and resists drying out

Arthropod Groups - Chelicerates

• Spiders, mites, and scorpions

• 2 body segments

• 6 pairs of jointed appendages

Arthropod groups - Myriapods

• Includes millipedes and centipedes

• Each segment has 1 or 2 pairs of legs

• Single pair of antennae and simple eyes

• Live in moist habitats under logs or stones

Arthropod groups - Crustaceans

• Includes, crabs, lobsters, shrimp, and barnacles

• 5 pairs of joined appendages

• 2 pairs of antennae

• Fewer body segments with those in the head and thorax to fuse and become specialized

Arthropod groups - Insects

• Includes beetles, bees, butterflies, moths, ants, and flies

• 3 body segments - head, thorax, and abdomen

• 3 pairs of legs ( 6 total )

• 1 or 2 pairs of wings