Introduction to AnimalsIntroduction to Animals

Chapter 25Chapter 25

Animal OverviewAnimal Overview

• Animal kingdom is Animal kingdom is extremely extremely diversediverse

• ALL Animals are:ALL Animals are:- Multicellular- Multicellular– EukaryotesEukaryotes– No cell wallNo cell wall

• Also share many other Also share many other characteristics…characteristics…

Characteristics of All Characteristics of All AnimalsAnimals

• 1)1) Multicellular OrganizationMulticellular Organization– Cells Cells specializespecialize to perform different to perform different

functionsfunctions• Allows organisms to adapt & evolveAllows organisms to adapt & evolve

– Different cells held together by Different cells held together by cell cell junctionsjunctions to form tissues to form tissues

• 2) Heterotrophy2) Heterotrophy– Herbivore Herbivore (only plants)(only plants) -Omnivore -Omnivore (both)(both)

– CarnivoreCarnivore (only meat)(only meat) -Decomposers -Decomposers (dead/decaying matter)(dead/decaying matter)

Characteristics of All Characteristics of All Animals (con’t)Animals (con’t)

• 3) Sexual Reproduction3) Sexual Reproduction– Gametes fuse to form zygote Gametes fuse to form zygote

(fertilized egg)(fertilized egg)– As zygote multiplies, cells As zygote multiplies, cells

differentiatedifferentiate into body partsinto body parts

• 4) Movement4) Movement– Nervous & Muscular system work Nervous & Muscular system work

together to control bodytogether to control body

Animal ClassificationAnimal Classification

• Animal Kingdom has 9 Animal Kingdom has 9 Phyla:Phyla:– 8 Invertebrate8 Invertebrate PhylaPhyla

(no backbone)(no backbone)• i.e.: earthworms, insectsi.e.: earthworms, insects

– 1 Chordata1 Chordata (spinal (spinal cord)cord)• IncludesIncludes Vertebrates Vertebrates

(have backbone)(have backbone)– i.e.: mammals, birds, fishi.e.: mammals, birds, fish

SymmetrySymmetry

• Asymmetry: Asymmetry: nonenone– i.e. spongesi.e. sponges

• Radial:Radial: radiate from radiate from center (no left/right, center (no left/right, etc)etc)– i.e. jellyfish, sea i.e. jellyfish, sea

anenomesanenomes

• Bilateral:Bilateral: 2-sided 2-sided– i.e. humans, lobsters, i.e. humans, lobsters,

butterfliesbutterflies