AP Biology 2007-2008

DomainBacteria

DomainArchaea

DomainEukarya

Common ancestor

Kingdom: AnimalsDomain Eukarya

AP Biology

Animal Characteristics Heterotrophs

must ingest others for nutrients Multicellular

complex bodies No cell walls

allows active movement Sexual reproduction

no alternation of generations no haploid gametophyte

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PoriferaCnidaria

Platyhelminthes

sponges jellyfish flatworms roundworms

NematodaMollusca Arthropoda Chordata

Annelida Echinodermata

mollusks

multicellularity

Ancestral Protist

tissues

bilateral symmetry

body cavity

segmentation

Animal Evolution

coelom

starfish vertebrates

endoskeleton

segmentedworms

insectsspiders

backbone

specialization & body complexity

specialized structure & function,muscle & nerve tissue

distinct body plan; cephalization

body complexity digestive & repro sys

digestive sys

body size

redundancy,specialization, mobility

body & brain size, mobility

radial

bilateral

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Body Cavity ectoderm

ectodermmesoderm

endoderm

ectodermmesoderm

endoderm

mesodermendoderm

acoelomate

pseudocoelomate

coelomate

coelom cavity

pseudocoel

Space for organ system development

increase digestive & reproductive systems increase food capacity

& digestion increase gamete

production Coelem

mesoderm & endoderm interact during development

allows complex structures to develop in digestive system ex. Stomach CLICK FOR VIDEO

protostome vs. deuterostome

AP Biology 2004-2005

What’s the most complex problem in biology?

AP Biology 2004-2005

The most complex problem

How to get from here to there

AP Biology 2004-2005

Egg zygote morula

AP Biology 2004-2005

Egg morula blastula Blastula formation

successive divisions result in a blastula hollow single-layered

sphere enclosing a space = blastocoel

AP Biology 2004-2005

AP Biology 2004-2005

Early embryonic stages Morula

solid ball stage Blastula

hollow fluid-filled ball stage by time human embryo reaches uterus

Gastrula development of primitive digestive tract

(gut) & tissue layers

AP Biology 2004-2005

Gastrulation zygote blastula gastrula

How you looked as a blastula…

AP Biology 2004-2005

Gastrulation zygote blastula gastrula

rearranges the blastula to form 3-layered embryo with a primitive gut

AP Biology 2004-2005

Gastrulation

blastopore:forms at sperm

penetration point

archenteron:forms endodermembryonic gut

mesoderm

dorsal lip: organizing center for developmenttissue formation

AP Biology 2004-2005

Primary tissue or “germ” layers ectoderm

external surfaces: skin epidermis (skin); nails, hair & glands; tooth enamel;

eye lens; epithelial lining of nose, mouth & rectum; nervous system

endoderm internal lining

epithelial lining of digestive tract & respiratory systems; reproductive system & urinary tract; digestive organs

mesoderm middle tissues: muscle, blood & bone

notochord; skeletal, muscular, circulatory, lymphatic, excretory & reproductive systems; lining of body cavity

AP Biology 2004-2005

Basic body plan Archenteron becomes

embryonic gut mouth at one end anus at the other

Protostomes “1st mouth” blastopore = mouth invertebrates

Deuterostomes “2nd mouth” blastopore = anus echinoderms &

vertebrates

AP Biology

Invertebrate: Porifera Sponges

no distinct tissues or organs do have specialized cells

no symmetry sessile (as adults)

food taken into each cell by endocytosis

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Invertebrate: Cnidaria Jellyfish, hydra, sea anemone, coral

tissues, but no organs two cell layers radial symmetry predators

tentacles surround gut opening

extracellular digestion release enzymes

into gut cavity absorption by cells

lining gut

medusapolyp

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hydra

stinging cellwith nematocyst

trigger

dischargednematocyst

undischargednematocyst

tentacles

mouth

sensorycell

stingingcell

Stinging cells of Cnidarians

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Invertebrate: Platyhelminthes

ectoderm

mesodermendoderm

Flatworms tapeworm, planaria mostly parasitic bilaterally symmetrical

have right & left & then have head (anterior) end & posterior end cephalization = development of brain concentration of sense organs in head

increase specialization in body plan

Animals nowface the world

head on!

acoelomate

AP Biology

Invertebrate: Nematoda Roundworms

bilaterally symmetrical body cavity

pseudocoelom = simple body cavity digestive system

tube running through length of body (mouth to anus) many are parasitic

hookworm

C. elegans

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Invertebrate: Mollusca Mollusks

slugs, snails, clams, squid bilaterally symmetrical (with exceptions) soft bodies, mostly protected by hard shells true coelem

increases complexity & specialization of internal organs

AP Biology

Invertebrate: Annelida Segmented worms

earthworms, leeches segments

increase mobility redundancy in body sections

bilaterally symmetrical true coelem

fan worm leech

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Invertebrate: Arthropoda Spiders, insects, crustaceans

most successful animal phylum bilaterally symmetrical segmented

specialized segments allows jointed appendages

exoskeleton chitin + protein

AP Biology

Arthropod groups

insects6 legs, 3 body parts

crustaceansgills, 2 pairs antennaecrab, lobster, barnacles, shrimp

arachnids8 legs, 2 body partsspiders, ticks, scorpions

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Invertebrate: Echinodermata Starfish, sea urchins, sea cucumber

radially symmetrical as adults spiny endoskeleton deuterostome loss of bilateral symmetry?

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Invertebrate quick check…

Which group includes snails, clams, and squid? Which group is the sponges? Which are the flatworms?

…segmented worms?…roundworms?

Which group has jointed appendages & an exoskeleton?

Which two groups have radial symmetry? What is the adaptive advantage of bilateral

symmetry? Which group has no symmetry?

Invertebrates: Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Mollusca, Arthropoda, Echinodermata

AP Biology

Vertebrates fish, amphibians,

reptiles, birds, mammals

internal bony skeleton backbone encasing

spinal column skull-encased brain

deuterostome

Chordata

postanaltail notochord

hollow dorsalnerve cord

pharyngealpouches

becomes brain & spinal cord

becomes vertebrae

becomes gills or Eustachian tube

becomes tail or tailbone

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Vertebrates: Fishsalmon, trout, sharks450 mya

Characteristics body structure

bony & cartilaginous skeleton jaws & paired appendages (fins) scales

body function gills for gas exchange two-chambered heart;

single loop blood circulation ectotherms

reproduction external fertilization external development in

aquatic egg

gillsbody

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Transition to LandEvolution of tetrapods

Tibia

Femur

Fibula

Humerus Shoulder

RadiusUlna

TibiaFemur

Pelvis

Fibula Lobe-finned fish

Humerus

Shoulder

Radius

Ulna

Pelvis

Early amphibian

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lung

buccalcavity

glottisclosed

Vertebrates: Amphibian Characteristics

body structure legs (tetrapods) moist skin

body function lungs (positive pressure) &

diffusion through skin for gas exchange three-chambered heart;

veins from lungs back to heart ectotherms

reproduction external fertilization external development in aquatic egg metamorphosis (tadpole to adult)

frogssalamanders toads

350 mya

AP Biology

Vertebrates: Reptiles Characteristics

body structure dry skin, scales, armor

body function lungs for gas exchange thoracic breathing; negative pressure three-chambered heart ectotherms

reproduction internal fertilization external development in

amniotic egg

250 mya dinosaurs, turtles lizards, snakesalligators, crocodile

embryoleatheryshell

chorion

allantoisyolk sac

amnion

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Vertebrates: Birds (Aves) Characteristics

body structure feathers & wings thin, hollow bone;

flight skeleton body function

very efficient lungs & air sacs four-chambered heart endotherms

reproduction internal fertilization external development in

amniotic egg

150 mya finches, hawk ostrich, turkey

trachea

anteriorair sacs

lung

posteriorair sacs

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Vertebrates: Mammals220 mya / 65 mya mice, ferret

elephants, batswhales, humans

musclescontract

diaphragmcontracts

Characteristics body structure

hair specialized teeth

body function lungs, diaphragm; negative pressure four-chambered heart endotherms

reproduction internal fertilization internal development in uterus

nourishment through placenta birth live young mammary glands make milk

AP Biology

Vertebrates: Mammals Sub-groups

monotremes egg-laying mammals lack placenta & true nipples duckbilled platypus, echidna

marsupials pouched mammals

offspring feed from nipples in pouch short-lived placenta koala, kangaroo, opossum

placental true placenta

nutrient & waste filter shrews, bats, whales, humans

AP Biology

Vertebrate quick check… Which vertebrates lay eggs with shells? Which vertebrates are covered with scales? What adaptations do birds have for flying? What kind of symmetry do all vertebrates have? Which vertebrates are ectothermic and which

are endothermic Why must amphibians live near water? What reproductive adaptations made mammals

very successful? What characteristics distinguish the 3 sub-

groups of mammals?

AP Biology 2007-2008

That’s the buzz!

AnyQuestions?