Intro to Animals (EUMETAZOA) Image from:

Porifera Cnidaria Platyhelminthes spongesjellyfishflatworms roundworms Nematoda MolluscaArthropodaChordata AnnelidaEchinoderm mollusks multicellularity Ancestral Protist tissues bilateral symmetry body cavity segmentation Animal Evolution eucoelom starfishvertebrates endoskeleton segmented worms insects spiders backbone Diagram from slide show by Kim Foglia

Animals Invertebrates (animals without a backbone) Porifera Cnidaria Worms Mollusks Echinoderms Arthropods

Animals Vertebrates- Animals with backbones Fish Amphibians Reptiles Birds Mammals

LIFE ON EARTH Image from:

Characteristics of ALL Animals: 1.Eukaryotic 2. Heterotrophic 3.Multicellular/differentiated cells 4.Cells have NO cell walls 5. Movement 6. Reproduction (Most sexual)

Kinds of Symmetry Asymmetry Radial Bilateral Images from:

DORSAL POSTERIOR VENTRAL ANTERIOR Animation from:

________________ Concentration of nervous tissue and sensory organs in anterior end of an organism (head area) First seen in Platyhelminthes (flat worms) Associated with bilateral symmetry Efficient response to stimulus Sense organs encounter environment first CEPHALIZATION

EMBRYOLOGY Image from: 1.Where does BLASTOPORE end up? 2.What do embryos look like as they divide? 3.When do cells decide what they will be?

Image from: EMBRYONIC DEVELOPMENT Becomes digestive system

1.Where does BLASTOPORE end up? Images modified from:

What do embryos look like as they divide? Images from: SPIRALRADIAL CLEAVAGE CLEAVAGE

When do cells decide what they will become? Image from:

Images modified from: Cells decide early Cells decide later Removing cell causes death Removing cell OK DETERMINATE INDETERMINATE

THAT’S WHERE TWINS COME FROM ! DIZYGOTIC TWINS (Fraternal twins) DIFFERENT DNA MONOZYGOTIC TWINS (Maternal twins) Identical DNA ONLY Deuterostomes can have identical twins!

ANIMALS (Triploblastic) Blastopore becomes MOUTH Blastopore becomes ANUS Decide very early (DETERMINATE) Decide later (INDETERMINATE) MOST INVERTEBRATES except ECHINODERMS ALL VERTEBRATES (Fish, amphibians, birds, reptiles, mammals) plus ECHINODERMS SPIRAL cleavage RADIAL cleavage PROTOSTOMES DEUTEROSTOMES

BODY PLAN INVERTEBRATES Dorsal heart Ventral nerve cord VERTEBRATES Ventral heart Dorsal nerve cord

Image from: GASTRULATION- cells move inward overlip of blastopore THREE germ layers form Becomes digestive system

All animals have 3 germ layers = TRIPLOBLASTIC Except: sponges, jellyfish, anemones = DIPLOBLASTIC Endoderm Mesoderm Ectoderm Muscle, excretory, bones, circulatory Digestive system, respiratory Outer skin, brain, nervous system

Types of Coeloms (See-Lums) No cavity (space) around organs Image from: ACOELOM = “without space”

FLATWORMS are ACOELOMATES!

Types of Coeloms (See-Lums) Space around organs but only lined with mesoderm on one side (lines body wall BUT NOT around gut) Image from: PSEUDOCOELOM

ROUND WORMS are PSEUDOCOELOMATES!

Kinds of Coeloms (See-Lums) EUCOELOM: Body cavity (space) lined on BOTH sides by mesoderm Image from: EUCOELOM = TRUE COELOM = COELOM

EUCOELOMATES ALL VERTEBRATES & MOST INVERTEBRATES

3 Types of Coeloms ectoderm mesoderm endoderm Image from: ACOELOM PSEUDOCOELOM EUCOELOM

FUNCTIONS of having a COELOM (body space): In animals without a skeleton- Fluid in coelom space can act as a HYDROSTATIC skeleton In animals without blood vessels- Fluid in coelom space can circulate nutrients and oxygen to cells Provides space/cushion internal organs

ADVANTAGE OF a EUCOELOM? Digestive organ muscles and body wall muscles come from MESODERM in different places so organism can digest food and move at same time. Images from:

ECTOTHERMIC ADVANTAGES: Slow metabolism means you can survive on 1/10 the food as a same size endotherm DISADVANTAGES: Can’t to live in extremely cold places (NO reptiles in Arctic) Can’t keep up max activity level for long

Endothermic “warm-blooded” Create own body heat FAST metabolism allows for: high activity for extended time ability to live in variety of environments EX: Birds, Mammals

SOURCES Crab from: Ant from: Clam from: Anemone from: Snail from:

Starfish from: Millipede from: Jellyfish from:

Turtle: Tree frog: Bird: Orangutan: Fish from:

Earthworm : /Exxon/Food%20Chain%20images/ExxonPicsLarge/Earthworms.jpg Crab from: Snail from: Starfish from:

All images on this page from: