Classification

• Classification: process of grouping things based on their similarities– (1.7 million kinds of organisms on Earth)

• Taxonomy: scientific study of how living things are classified

• Aristotle divided animals into 3 groups…those that ~fly ~swim ~walk, crawl, or run

• Linnaeus: placed organisms in groups based on features• Binomial nomenclature: 2 part name• i.e. Felis (genus) domesticus (species)– Latin words used reflect time period of scientists– Name is written in italics– Genus in capitalized, species name not capitalized– Species=produce fertile offspring when mating

Guess What These Mean…

• Felis domesticus: • house cat• Felis concolor: • “one-color” = puma• Felis pardalis: • “spotted coat” = ocelot• Musca domestica: • housefly• Hirudo medicinalis:• medicinal leech

7 Levels of Classification

• First organism is placed in a broad group which is divided into more specific groups

• The more levels that 2 organisms share, the more they have in common

1. Kingdom (King)

2. Phylum (Philip)

3. Class (Came)

4. Order (Over)

5. Family (For)

6. Genus (Good)

7. Species (Spaghetti) Transparency of owls—7 levels of classification

• The modern system of classification does two jobs:1. Groups organisms according to their basic

characteristics2. Gives a unique name to an organism that

scientists all over the world can use and understand

– The words for an organisms genus and species make up its scientific name; i.e. Homo sapien

Human Classification

• Kingdom…Anamalia• Phylum…Chordata– Subphylum…Vertebrata

• Class…Mammalia– Subclass…Eutheria

• Order…Primates– Suborder…Anthropoidea

• Family…Hominidae• Genus…Homo• Species…Homo sapien

Today, there are 6 kingdoms: organisms are placed into kingdoms based on …

• their type of cells• their ability to make food• the number of cells in their bodies

6-Kingdom ClassificationKingdom Cells per

OrganismCell Type Nutrition Type Examples

Archae-bacteria

Unicellular Prokaryotic AutotrophicHeterotrophic

Eubacteria Unicellular Prokaryotic AutotrophicHeterotrophic

Streptococci

Protists UnicellularMulticellular

Eukaryotic AutotrophicHeterotrophic

AmebaAlgae

Fungi UnicellularMulitcellular

Eukaryotic Heterotrophic Yeast Mushrooms

Plantae Multicellular Eukaryotic Autotrophic

Anamalia Multicellular Eukaryotic Heterotrophic

• Used to be 5 kingdom: Monera=both bacteria groups

• Archaebacteria: “ancient bacteria” may resemble Earth’s early life forms

• Unicellular: composed of a single cell• Multicellular: composed of more than one cell• Prokaryotic: no nuclear membrane, few organelles• Eukaryotic: has nuclear membrane, many organelles• Autotrophic: food is manufactured i.e.

photosynthesis• Heterotrophic: cannot manufacture food. Feeds on

others

Prokaryotic vs. Eykaryotic

Classification: Modern Approaches

Direct study of genetic material-(DNA, RNA, Proteins)

They compare regions of DNA or RNA by looking at Nitrogen base pairs (C,T,G,A)They look at Proteins and the sequence of amino acids

Bacteria

• Prokaryotes• There are more bacteria living in your mouth

than there are people living on Earth…Yikes!• 3 shapes: spherical, spiral, rod-like• Flagellum: helps with movement, like a

propeller (not all bacteria have flagellum)• Archaebacteria: live in extreme environments

i.e. hot springs, acidic places, intestines, swamps, sewage

• Eubacteria: do not live in extreme environments i.e. cat skin, swarm in nose

Facts about Bacteria………….

ROD-LIKE SPHERICAL

SPIRAL

• Fun Fact: methane produced by archaebacteria that died millions of years ago is the major component in about 20% of Earth’s deposit of natural gas

• Some bacteria is good-cheese, yogurt, pickles…food digestion

• Antibiotic: chemical that can kill bacteria without harming cells i.e. (Penicillin) causes bacteria to burst

Structure of a Bacteria Cell

• Flip chart section on Bacteria

• Viruses: small, non-living particle that invades and then reproduces inside a living cell– They are not cells-they can only multiply when

they are inside a living cell• Host: living thing that provides energy for

virus i.e. cold virus infect cells in nose and throat of humans

• Bacteriophage: virus that infects bacteria – Incredibly small in size

• Virus structure: 2 parts…– Outer coat: protects virus– Inner core: genetic material

• Like keys, a viruses proteins only fit into certain “locks” or proteins on the surface of a host’s cell– i.e. HIV virus can only attach to specific cells in the human

body– Once inside, a virus’s genetic material takes over the cell’s

functions. The genetic material directs the cell to produce the virus’s proteins and genetic material, then new viruses form

• Active virus: immediately goes into action – Virus takes over cells functions

• Hidden virus: virus’s genetic material becomes part of the cell’s genetic material– May stay inactive for a long time, then will suddenly

become active (cold sores)– There are no medications currently that can cure viral

infections• Vaccine: made from dead or altered virus or

bacteria. When injected it should not cause disease, but instead activate the body’s natural defenses. Put the body “on alert”

• Flipchart, section on viruses

• Protists– Eukaryotes– Unicellular of Multicellular– Heterotrophs or autotrophs– Likes environments with moist surrounding

• 3 categories: animal-like, fungus-like, and plant-like–Protozoan's=animal-like protists that are

unicellular………….

4 main Protozoan Groups:(Animal-like protists)

Protozoan groups Type of Movement Example– Sarcodine -pseudopod - ameba– Ciliates -cilia - paramecium– Zooflagellates -flagella -trypanosome– Sporzoans -parasites -plasmodium (feeds on cells) (causes malaria)

(variety of movement)

Protozoans cont.

• Pseudopod means “false foot” = bulges of the cell membrane fill with cytoplasm

• Cilia act like tiny oars to move organism• 1-8 whip-like flagella that move organism• Parasites feed on cells, variety of movement

Protozoans-Ameba

• Plant-like protists (algae)– Autotrophs mainly

• Euglena– Green– Unicellular algae– Autotrophs when sunlight is available (unique)– Heterotrophs-can find food in environment if the sun

isn’t available (unique)• Eyespot: not really an eye, but pigment that is

sensitive to light and helps the organism find the correct light source

• Green/red/brown algae (unicellular/multicellular)

Brown Algae

More plant-like protists

• Diatoms

• Dinoflagellates

Red Tide from Dinoflagellates

• Flipchart, section on protists

Funguslike Protists

• Fungi…..”sort of like” animals: Heterotrophs“sort of like” plants: Have cell wallsand most use spores to reproduce.

Slime moldsWater moldsDowny mildew

Slime Mold (notice

the Hyphae)

Downy MoldsWater Molds ↓ →

• Fungi: (that are not protists)– i.e. Yeast = unicellular– i.e. Mold and Mushrooms = multicellular

• Hyphae-cells are arranged as part of structureContinuous threads of cytoplasm that

contain many nuclei

• Reproduction of Fungi– Asexual=budding i.e. yeast– Sexual=hyphae grow together and produce spores

• For example…The stalks and caps of the mushrooms are made of hyphae packed so tightly that they appear solid. Underground, however, a mushroom’s hyphae form a loose, threadlike maze in the soil.

3 Major Groups of Fungi1. Sac fungi: spores in long sacs2. Club fungi: spores in club structure3. Zygote: bread mold-

Largest group of Fungi: includesYeast, morels, and truffles

Zygote Fungi: Common fruit and bread molds. Can survive harsh environmental conditions← →

Club Fungi: produceMicroscopic spores in structures that look like clubs

Fungi in Nature

– Decomposers– Parasite=Dutch elm, athletes foot– Food: yeast, cheese– Penicillin mold=antibiotic