the classification of living organisms r. llopis-garcia a2 biology

The Classification of The Classification of living organismsliving organisms

R. LlopisR. Llopis--GarciaGarcia

A2 BiologyA2 Biology

SpeciationSpeciation

Natural selection provides a mechanism Natural selection provides a mechanism by which NEW populations of a species by which NEW populations of a species can arise.......can arise.......

But at what point these new populations But at what point these new populations can be consider a new species?can be consider a new species?

Well how would you define “species”?....Well how would you define “species”?....

The concept of speciesThe concept of species

The Institute of Biology define species as...The Institute of Biology define species as...

““AN INTERBREEDING GROUP WHICH AN INTERBREEDING GROUP WHICH PRODUCES VIABLE AND FERTILE PRODUCES VIABLE AND FERTILE OFFSPRING WHICH SHARE A OFFSPRING WHICH SHARE A COMMON ANCESTRY AND ARE COMMON ANCESTRY AND ARE SIMILAR IN ANATOMY AND SIMILAR IN ANATOMY AND BIOCHEMISTRY”BIOCHEMISTRY”

Can you name the species?Can you name the species?

Homo Homo sapienssapiens


PhanthePhanthera leora leo


FelisFelis

domesticdomesticusus

Mules are not a species!Mules are not a species!

If two groups cannot If two groups cannot interbreed to produce interbreed to produce fertile and viable fertile and viable offspringoffspring, they must be , they must be different species!!!different species!!!

Reproductive isolationReproductive isolation

Is a period where the populations are Is a period where the populations are prevented from interbreedingprevented from interbreeding

During that period, genetic During that period, genetic differences between the populations differences between the populations can increase due to mutation and can increase due to mutation and selection.selection.

Eventually, the two populations are Eventually, the two populations are unable to interbreed and have unable to interbreed and have becomebecome distinc species!!!distinc species!!!

How reproductive isolation How reproductive isolation arise?arise?

2 main types:2 main types:

1.1.ALLOPATRIC ALLOPATRIC SPECIATIONSPECIATION

2.2.SYMPATRIC SYMPATRIC SPECIATIONSPECIATION

ALLOPATRIC SPECIATIONALLOPATRIC SPECIATION

Geopraphycal isolation occurs when Geopraphycal isolation occurs when the two populations are PHYSICALLY the two populations are PHYSICALLY separated.separated.

Examples......Examples......

Sympatric speciationSympatric speciation

Does not involve physical Does not involve physical separation (the 2 population may separation (the 2 population may inhabit the same area). inhabit the same area). Reproductive isolation can arise in Reproductive isolation can arise in different ways:different ways:

1)1) Seasonal isolationSeasonal isolation

2)2) Temporal isolationTemporal isolation

3)3) Behavioural isolationBehavioural isolation

Seasonal isolationSeasonal isolation

Members of the Members of the two population two population reproduce at reproduce at different times different times of the year.of the year.

Can you think of Can you think of an example?an example?

Temporal isolationTemporal isolation

Members of the Members of the two populations two populations reproduce at reproduce at different times different times of the day.of the day.


Behavioural isolationBehavioural isolation

Members of the Members of the two populations two populations have different have different courtship courtship patterns.patterns.


TAXONOMYTAXONOMY

Taxonomy is that Taxonomy is that branch of biology branch of biology dealing with the dealing with the identification and identification and naming of organisms.naming of organisms.

classificationclassification LinneusLinneus attempted to attempted to

pigeon-hole (or pigeon-hole (or classify) all known classify) all known species of his time species of his time (1753). Linnean (1753). Linnean hierarchical hierarchical classification was classification was based on the premise based on the premise that the species was that the species was the smallest unit, and the smallest unit, and that each species (or that each species (or taxon) nested within a taxon) nested within a higher category.higher category.

exampleexample

Kingdom AnimaliaKingdom Animalia

Phylum Chordata Phylum Chordata

Class Mammalia Class Mammalia

Order Primates Order Primates

Family Hominidae Family Hominidae

GenusGenus HomoHomo

speciesspecies sapienssapiens

The Kingdoms of Life The Kingdoms of Life

Living things are classified into 5 Living things are classified into 5 kingdoms:kingdoms:

1.1. Kingdom ProkaryoteKingdom Prokaryote2.2. Kingdom ProtoctistaKingdom Protoctista3.3. Kingdom FungiKingdom Fungi4.4. Kingdom PlantaeKingdom Plantae5.5. Kingdom AnimaliaKingdom Animalia

Kingdom ProkaryoteKingdom Prokaryote Also called MONERAAlso called MONERA All organism in this kingdom are All organism in this kingdom are

unicellular or filamentousunicellular or filamentous The cells lack true nucleiThe cells lack true nuclei Cells have no membrane bound Cells have no membrane bound

organellesorganelles Cell walls are not made of Cell walls are not made of

cellulosecellulose

Blue green bacteriaBlue green bacteria

Bacteria reproducingBacteria reproducing

cyanobacteriacyanobacteria

ProkaryotaeProkaryotaeCell structure

•Prokaryotic

•unicellular or colonial

Cell wall

•Present (Peptidoglycans)

Nutrition

•Autotrophic (chemosynthesis/photosynthesis)

Other notes

• Contains only the bacteria

• About 10,000 known species

Prokaryotae Phyla Prokaryotae Phyla Cyanobacteria

•Unicellular or colonies

•Aquatic

•Plantlike photosynthesis

•Possible origin of plants

•Often produce ‘blooms’- population explosions of millions of cyanobacteria

Prokaryotae Phyla Prokaryotae Phyla Proteobacteria

•Purple bacteria

•often flagellated and found in pond sediments

•Chemoautotrophic

•Free-living/symbiotic species (eg Rizobium)

•Play key role in chemical cycles of ecosystems

•Chemoheterotrophic

•Include intestinal bacteria (eg Salmonella)

•Mostly rod-shaped

•Often pathogenic

Prokaryotae Phyla Prokaryotae Phyla Spirochetes

•Helical chemoheterotrophs

•Free-living species and pathogens

•Corkscrew-like movements due to intenal flagella like filaments

Borrelia burgdoferi (casues Lyme disease)

Prokaryotae Phyla Prokaryotae Phyla Gram-positive bacteria

•Mostly chemoheterotrophs

•Include mycolpasmas (often pathogenic) smallest of all known cells (0.10-0.25m)

•Some photosynthetic

•Includes soil bacteria that resemble fungi

•Includes actinomycetes, important sources of antibiotics

Clostridium botulinium Microplasma pneumoniaeStreptomyces sp.

Prokaryotae Phyla Prokaryotae Phyla Chlamydias

•Intracellur parasites of animals

•Obtain ATP from host cells

•Lack peptidoglycan in cell walls

Chalmydia trachomatis

Most common cause of blindness in the world and also of the sexually transmitted disease

Kingdom ProtoctisKingdom Protoctis

Very diverse groupVery diverse group In this group if the can not In this group if the can not

fit in any other group fit in any other group (dump bin)(dump bin)

All eukaryotesAll eukaryotesSome heterotroph, some Some heterotroph, some

light autotrophlight autotroph

amoebaamoeba

EphidiumEphidium sp sp

ParameciumParamecium, a typical , a typical ciliate ciliate

AlgaeAlgae

Dinoflagellate, Dinoflagellate, PeridiniumPeridinium sp sp

Red algaeRed algae

Brown algaeBrown algae

Cell structure

•Eukaryotic

•Unicellular, colonial and multicellular forms

Cell wall

•Sometimes present (Polysaccharides)

Nutrition

•Autotrophic

•Hetorotrophic

Other notes

• Classed here if they can’t be placed in any other kingdom therefore are the most diverse group (30 phyla)


ProtoctistaProtoctista

Protoctista (Continued) Protoctista (Continued) Among the protoctists are:

•Unicellular

•Multicellular: cells arranged in filaments

•Multicellular: cells arranged in ball like colonies

•Mulicellular: cells arranged into tissues

They can behave like:

•Animals

•PlantsOr can be:

•Slime moulds

•Protozoa

•Algae

Protoctista (Continued) Protoctista (Continued)

Pond weed, Spyrogyra sp- filamentous protoctist

Bladder wrack, Fucus vesiculosus- photosynthetic multicellular protoctist

Euglena sp, freshwater species,plant-like and animal-like Fruiting structure (sporangium) of a

slime mould

Kingdom FungiKingdom Fungi

Common features:Common features: A non cellulose cell wallA non cellulose cell wall Non photosyntheticNon photosynthetic Eukaryotes (filaments or hyphae Eukaryotes (filaments or hyphae

often multinucleated)often multinucleated) Secrete enzymes to digest Secrete enzymes to digest

organic matterorganic matter

SEM image of a bread mold SEM image of a bread mold fruiting structure, fruiting structure, Rhizopus Rhizopus

stoloniferstolonifer

Amanita phalloidesAmanita phalloides is the most is the most poisionous of all mushrooms poisionous of all mushrooms

lichenslichens

Cell structure

•Eukaryotic

•Mostly multicellular but some unicellular (eg yeast)

Cell wall

•Present (Chitin)

Nutrition

•Heterotrophic

Other notes

• Most made of mass of thread like filaments called hyphae.

• Lack cilia and flagella at all life cycle stages

• Reproduce by forming spores, produced by mitosis


FungiFungi

Fungi Phyla Fungi Phyla Chytridiomycota

•Absorptive mode of nutrition

•Some are unicellular but most form hyphae (multicellular)

•Mainly aquatic, some parasites, some saprobes

•Most primitive form of fungi, possibly evolving from protists with flagella

•Only fungi with flagella

Branched hyphae

Chytridium sp.

Fungi Phyla Fungi Phyla Zygomycota

•Zygote fungi

•Mostly terrestrial, living in soil or decaying matter

•Includes the mycorrhizae, mutualistic associations with plant roots

•Some can aim their spores and shoot them up to 2m to aid dispersion

Sporangial

fruiting structure

Bread mold, Rizopus stolonifer

hyphae

Fungi Phyla Fungi Phyla Adcomycota•Over 60,000 species

•Sac fungi- produce spores in saclike asci

•Produce huge numbers of asexual spores for reproduction

•Marine, terrestrial and freshwater

•Unicellular yeast to elaborate cup fungi and morels

•Include many plant pathogens

•Half live sybiotically with algae as lichens

Cookeina sulcipes

Brewers yeast

Morchella esculenta

Fungi Phyla Fungi Phyla Basidiomycota•25,000 species

•Includes mushrooms, puffballs and shelf fungi

•Important decomposers of wood and plant material

•Includes some destructive plant parasites

•Can reproduce sexually by producing elaborate fruiting bodies- basidiocarps, the sources of sexual spores

Sulphur shelf fungus

Common mushroom

Gills lined with basidia

Kingdom PlantaeKingdom Plantae

All plants:All plants:Are multicellularAre multicellularHave eukaryote cells with Have eukaryote cells with

a CELLULOSE cell walla CELLULOSE cell wallAre photosyntheticAre photosynthetic

Flowering plants, the angiosperms, Flowering plants, the angiosperms, were the last of the seed plant groups were the last of the seed plant groups to evolve, appearing over 140 million to evolve, appearing over 140 million years ago during the later part of the years ago during the later part of the

of the Age of Dinosaurs (the beginning of the Age of Dinosaurs (the beginning of the Cretaceous, 140 million years of the Cretaceous, 140 million years

ago). All flowering plants produce ago). All flowering plants produce

flowers.flowers.

Cell structure

•Eukaryotic

•Multicellular

Cell wall

•Present (Cellulose)

Nutrition

•Autotrophic (photosynthesis using cholorplasts)

Other notes


• Develop from multicellular embryos

• Complex lifecycle that involves 2 different types of adult, one haploid and one diploid.

PlantaePlantae

Plantae Phyla Plantae Phyla Mosses•Bryophytes

•Gametophyte is the common generation

•Mass of many plants growing together

•Absorbs/retains rain water

•Grip with rhizoids

•Peat mosses take up 3% of Earths terrestrial surface!

Peat moss

Sphagnum squarrosum

Plantae Phyla Plantae Phyla Liverworts•Bryophytes

•Gametophyte is the common generation

•Most species found in tropical forests

•Bodies often divided into lobes

•Can reproduce asexually from bundles of cells called gemmae

Marchantia polymorpha

gemmaa cups

Plantae Phyla Plantae Phyla Ferns

•Vascular seedless plants

•Sporophyte (diploid generation) is the larger and more complex generation

•More common in relatively damp habitats

•Leaves called fronds, divided into leaflets

•12,000 species

Lady fern: Athyrium filix-femina

fronds

Plantae Phyla Plantae Phyla Conifers

•Vascular seed plants

•Bear their seeds ‘naked’ on surface of sporophytes

•Reproductive structure is the cone

•Contains pines, firs, spruces, larches and cedars among others

•Most are large trees

•Nearly all evergreen

•Dominate vast forested regions of northern hemisphere

Pine cone

Redwood forest

Plantae Phyla Plantae Phyla Flowering Plants

•Angiosperms

•Most diverse & widespread group of plants (250,000 species)

•Monocots (eg palms, grasses, grain crops, orchids)

•Dicots (eg roses, peas, maples, buttercups, sunflowers, and oaks)

•Flower is reproductive structure

•Fruits (mature ovaries) with seeds (mature ovules) encased in ripen ovary. Eg pea pod/peas

Orchid

Sunflower

Kingdom AnimaliaKingdom Animalia

All animals:All animals: Are multicellularAre multicellular Have eukaryotic cells with NO cell wallHave eukaryotic cells with NO cell wall Develop from a blastocyst (a hollow ball Develop from a blastocyst (a hollow ball

of cells)of cells)Most animals:Most animals:-ingest their food into a digestive system-ingest their food into a digestive system-are motile-are motile

HydraHydra

The Class GastropodaThe Class Gastropoda

The Class CephalopodaThe Class Cephalopoda

Phylum Annelida: Segmented Phylum Annelida: Segmented Worms Worms

Phylum Arthropoda: Phylum Arthropoda: Segmented Bodies with Segmented Bodies with

Segmented Appendages Segmented Appendages

Jumping Spider, Jumping Spider, Plaexippus Plaexippus paykullipaykulli

The Class InsectaThe Class Insecta

Fruit Fly, Fruit Fly, Drosophila Drosophila melanogastermelanogaster

Phylum Chordata Phylum Chordata

Class Chondrichthyes: Class Chondrichthyes: Cartilaginous FishCartilaginous Fish

Class Osteichthyes, the Class Osteichthyes, the Bony FishBony Fish

Class Amphibia: Animals Class Amphibia: Animals Move AshoreMove Ashore

Class Reptilia: Reproducton Class Reptilia: Reproducton Without WaterWithout Water

Class Aves: Birds of a Class Aves: Birds of a FeatherFeather

Class Mammalia: Got Milk?Class Mammalia: Got Milk?

Class Mammalia contains around 5000 Class Mammalia contains around 5000 species placed in 26 orders (usually). species placed in 26 orders (usually). The three unifying mammalian The three unifying mammalian characteristics are:characteristics are:

hairhair the presence of three middle ear the presence of three middle ear

bonesbones the production of milk by mammary the production of milk by mammary

glandsglands

Mammalian AdaptationsMammals developed several adaptations that

help explain their success.Teeth are specialized for cutting, shearing or

grinding; thick enamel helps prevent teeth from

wearing out.Mammals are capable of rapid locomotion.Brain sizes are larger per pound of body

weight than most other animals'.Mammals have more efficient control over

their body temperatures than do birds.Hair provides insulation.

Mammary glands provide milk to nourish the young.

Subclass Metatheria: Subclass Metatheria: Marsupials Marsupials

Subclass Eutheria Subclass Eutheria

And…….And…….

Cell structure

•Eukaryotic

•Multicellular

Cell wall

•Absent

Nutrition

• Heterotrophic

• Involves a digestive cavity

Other notes

• Develop from embryos that at some stage formed a blastula

• Have nervous and hormonal control systems

• About 35 phyla

AnimaliaAnimalia

Animalia Phyla Animalia Phyla Proifera (Sponges)

•Closest to the protists

•Sessile with porous bodies through which water is pumped and food is filtered.

•9000 species, all aquatic, only 100 freshwater species

•No specialised organs or tissues

•Mostly hermaphrodites

•Capable of regenerationPurple tube sponge

Elephant ear sponge

Animalia Phyla Animalia Phyla Cnidaria (Jellyfish, Corals, Anemones)

•10,000 species

•Radially symmetrical

•Gastrovascular cavity (central digestive compartment)

•2 body types: polyp (anchored)

medusa (free floating)

•Carnivores, using tentacles to capture prey

•Muscles and nerves occur in their simplest forms

Jellyfish:

medusa form

Tube coral: poly form

Animalia Phyla Animalia Phyla Platyhelminthes (Flatworms)

•Aceolomates (have no body cavity)

•Bilateral symmetry, dorsoventrally flattened

•20,000 species (including tapeworms and flukes)

•Free-living and parasitic species ranging from microscopic to 20 metres in length

•Primitive brains

•Opening to body cavity serves as mouth and anus!

Pseudoceros ferrugineus: free living

Tapeworm: parasitic

Animalia Phyla Animalia Phyla Nematoda (Roundworms)

•Cylindrical body, tapered tail and blunt head

•90,000 species known

•1mm to 1 metre in size

•Complete digestive tract (separate mouth and anus)

•No circulatory system

•Parasitic and free-living types

•Usually sexual reproduction

Phasmarhabditis sp. Lives in soil

Typical nematode

Animalia Phyla Animalia Phyla Mollusca (Clams, snails, octopuses, squid, slugs)

•150,000 diverse species

•Muscular foot for movement

•Visceral mass (containing most of the internal organs)

•Mantle (fold of tissue that drapes over the visceral mass and often secretes a shell)

•Many feed using radula to scrape up food

•Many have separate sexes but many are hermaphrodites

Edible snail

Foot Visceral mass

Oval squid, sepioteuthis lessoniana

Animalia Phyla Animalia Phyla

•15,000 species including earthworms and leeches

•1mm to 3 metres in length

•Segements called metameres each contain a cluster of nerve cells and excretory organs

•Ventral nerve, blood vessels and digestive tract pass though the segments

•Earthworms are hermaphrodites but can cross-fertilise Tube fanworm

Annelida (segmented worms)

Earthworm, Lumbricus terrestris


•1 million species, most successful phyla

•Regional segmentation (head, thorax, abdomen)

•Jointed appendages

•Exoskeleton (layers of protein and chitin)

•Bilaterally symmetrical

•Open circulatory systems (with hemolymph)

•Variety of gas exchange organsTrilobite, Modocia centralis

a fossil Arthropod

Arthropoda (crustaceans, insects, spiders)

Hawaiian lobster, Enoplometopus occidentalis


Leopard sea cucumber

Echinodermata (sea stars, sea urchins) Pink sea star

•6,000 species

•Radially symmetrical when fully grown

•Almost all marine species

•Sessile or slow moving

•Endoskeleton of hard calcareous plates covered by thin skin

•Water vascular system (network of hydraulic canals) branching into tube feet that function in locomotion, feeding and gas exchange

Sea urchins


Human foetus

Chordata (lancelets, tunicates, vertebrates) Sea squirt (tunicate)

•4 distinguishing features (often only in embryonic development)

• Hollow dorsal nerve cord

• Notocord (flexible rod between digestive tube & nerve cord)

• Pharyngeal Slits (gill slits)

• Post anal tail

Lancelet

•Vertebrates include fish, amphibians, reptiles birds and mammals

•Includes Homo sapiens

Complete the Complete the classification….classification….

Kingdom:Kingdom: Phylum:Phylum: Class:Class: Order:Order: Family:Family: Genus:Genus: Specie:Specie:

Felis lynxFelis lynx

K: AnimaliaK: Animalia P: ChordataP: Chordata C: MammalianC: Mammalian O: CarnivoraO: Carnivora F: FelidaeF: Felidae G: FelisG: Felis S: Felis lynxS: Felis lynx

Find in the internet the Find in the internet the classification of the following classification of the following

animalsanimals

The endThe end

the classification of living organisms r. llopis-garcia a2 biology

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