Monday, April 8 th

MONDAY, APRIL 8TH

Introduction to Animals

Objective: Be able to identify if an organism is in the animal kingdom based off characteristics

10 Animal Phylu

ms

WHAT IS AN ANIMAL

MulticellularHeterotrophic EukaryoticReproduce sexually and asexuallyLack cell walls

SYMMETRYAsymmetry-no body plan(sponges)Radial Symmetry-radiate from center

(jelly fish)Bilateral Symmetry-identical halves

when cut from head to tail.

Anatomical Terminology

Superior (toward head) Inferior (toward feet) Dorsal (toward back) Ventral ( toward front) Medial (towards center) Lateral (towards outside)ProximalDistal

BODY PLANcoelom - body cavity to house organs. An evolutionary advantageacoelomate - no body cavity presentPseudocoelomate – partial body cavity

Introduction to Animals Germ Layers

Endoderm inner layer of cells

Ectodermouter layer of cells

Mesoderm layer of cells

between the endoderm and ectoderm

10 Animal Phylu

ms

PHYLUM PORIFERA

FEEDING: water is drawn in through pores into a central cavity and out of opening called OSCULUM

Lack TRUE Tissues Sessile (doesn’t

move)

SPONGES

2 Tissue LayersHermaphrodites

Ectoderm & Endoderm

Egg & Sperm – Sexual reproduction results when sperm are drawn to other sponge

Capable of RegenerationNO Tissues or coordination between parts

Check these

Porifera out

PHYLUM CNIDARIAHYDRA, SEA

JELLY (JELLYFISH),

CORALS

2 Germ Layers**Muscles & Nerves

Endotherm & Ectotherm

Simplest Form**Radial Symmetry

** evolutionary advancement

Body is a sac with a central gastrovascular cavity and 1 opening (mouth and anus)

Carnivores: use nematocysts (tentacles) to capture prey

Can occur as POLYP (sessile) or MEDUSA (free swimming)

Reproduce by spawning

PHYLUM PLATYHELMINTHESFlatworms, flukes, tapewormsBilateral symmetry*3 tissue layers*

ectoderm/mesoderm/endodermmore complex organ systems

and true muscles*

only 1 openingReproduction:sexually - exchange sperm through internal fertilization

asexually - regenerationHermaphrodites

PHYLUM NEMATODA

roundwormsMost numerous of all animalscomplete digestive tract; 2 OPENINGS*

Reproduction is usually sexual w/ separate males and females

Fertilization is internalPseudocoelom*

parasitic worms

PHYLUM ANNELIDA Segmented worms: earthworm, leech all have segments* Coelom (body cavity) - houses, cushions and protects

organs* Digestive system has specialized regions;Pharynx,

esophagus, crop, gizzard and intestines

Closed circulatory system; blood*

“brainlike” cerebral gangliaHermaphroditic but cross fertilize (exchange sperm and store it in clitellium)

The Giant Earthworm

PHYLUM MOLLUSCASnails, oysters, octopuscoelom*BODY: 3 main parts FOOT (movement)VISCERAL MASS (internal organs)MANTLE (shell)

Separate sexes with ovaries and testes in visceral mass -- reproduce sexually

1. Class Gastropoda - snails, slugs• single shell

CLASSES of Mollusks

2. Class Bivalvia - oysters, clams• suspension feeders • two shells

3. Class Cephlapoda - octopus, squid• built for speed -- carnivores,• reduced shell (beak)

PHYLUM ECHINODERMATA

Sea stars, sea urchinsRadial symmetryplates with spines embedded in soft body tissues.

External fertilization; separate males and females

simple nervous and sensory system; no excretory system

Gill-like structuresa sea star is a predator; it spits its stomach from its mouth and digests its food and brings the stomach back in.

PHYLUM ARTHROPODAMost successful group of animals ever to live

segmentation, hard skeleton and jointed appendages led to great success.

Appendages are modified for walking, feeding, flying, sensory reception, copulation and defense

Body covered with cuticle (exoskeleton) made of chitin; provides protection and place for muscle attachment

Grow by moltingSeparate sexes: males and females

Well developed sensory organs including eyes, olfactory receptors (scent), antennae (touch).

Cephalization is extensive (well defined head)

CLASS ARACHNIDAspiders, ticks, mites, scorpions

2 body parts (cephalothorax and abdomen)

anterior appendages are modified as pincers or fangs (chelicerae)

CLASS DIPLOPODA (millipedes)2 pair of legs per segmentsaprophytesCLASS CHILOPODA (centipedes)

1 pair of legs per segmentcarnivorous, poisonous

Class Insectaout number all other life forms combined

complex NS3 body regions (head, thorax and abdomen)

specialized mouthparts (mandibles for eating)

3 pairs of legsPollination

CLASS CRUSTACEA Lobsters, crawfish, shrimp, crab Most are aquatic Head and thorax fused into 1 cephalothorax

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