Characteristics of Living Organisms

•What is one reason people group things into categories?

•What characteristics do you think scientists look at when classifying organisms?

TEKS 6.12C recognize the broadest taxonomic classification of living organisms is divided into currently recognized Domains TEKS 6.12D identify the basic characteristics of organisms, including prokaryotic or eukaryotic, unicellular or multi-cellular, autotrophic or heterotrophic, and mode of reproduction, that further classify them in the currently recognized Kingdoms

Taxonomy is the science of classifying and naming organisms.

A taxonomist is a scientist who classifies or names organisms.

Scientists look at characteristics such as…

• Multi-cellular• Unicellular

• Autotrophic • Heterotrophic

• Sexual reproduction

• Asexual reproduction

• Prokaryotic• Eukaryotic

The following slides review the characteristics of each of the three domains and six kingdoms.

Living organisms

Important characteristicsProkaryotic cells Eukaryotic cells

Domain bacteria Domain ArchaeaDomain Eukarya

Kingdom Animalia

Kingdom Protista

Kingdom Plantae

Kingdom Fungi

Kingdom Eubacteria Kingdom

Archaebacteria

Prokaryotic – lack a nucleus Unicellular – single celled Some autotrophic, some heterotrophic Reproduce asexually Some live in extreme environments

◦ High salinity (salt content)◦ Low oxygen concentrations◦ High temperatures◦ High or low pH◦ Guts of grazing herbivores- produce methane

Many live in oceans

Domain ArchaeaKingdom Archaebacteria

Prokaryotic – lack a nucleus Unicellular – single celled Some autotrophic, some heterotrophic Reproduce asexually Used in food production, oil spill cleanup,

and sewage treatment plants Decomposers – break down dead organisms Some cause disease – strep throat, food

poisioning, etc.

Domain BacteriaKingdom Eubacteria

http://biodidac.bio.uottawa.ca/

Eukaryotic – have a nucleus Most unicellular, some multi-cellular Some autotrophic, some heterotrophic Reproduction can be asexual or sexual

Examples: amoeba, paramecium, algae, diatoms, and many more

Domain EukaryaKingdom Protista

Eukaryotic – have a nucleus Some unicellular, most multi-cellular Heterotrophic Reproduction can be asexual or sexual Many are decomposers Examples: mold, mushrooms, yeast

Domain EukaryaKingdom Fungi

Eukaryotic – have a nucleus Multi-cellular Almost all are autotrophic Reproduce sexually and asexually Most need sunlight, water, minerals and

carbon dioxide to survive Examples: trees, grasses, mosses, ferns,

cactus, etc.

Domain EukaryaKingdom Plantae

http://biodidac.bio.uottawa.ca/

Eukaryotic – have a nucleus Multi-cellular Heterotrophic Most reproduce sexually but some asexually Examples: lizards grasshoppers, spiders,

dogs, humans, worms, clams, fish, etc.

Domain EukaryaKingdom Animalia

An organism is eukaryotic, multicellular and heterotrophic. In which of the kingdoms would you place this organism?

Practice question

Fungi or animal