Classification Notes

1.         There are over 1.5 million species that have been described and named by science.

2.         Because there are so many different species, we need to be able to classify and organize them.

3.         The science of classifying living things is called taxonomy and scientists who classify things are called taxonomists.

4.         Why do we need to classify things?

            a.         It's a good way to organize things to make studying them easier.

            b.         It's easier to identify unknown organisms.

            c.         It helps to show relationships between organisms.

5.         Carolus Linnaeus (1707-1778) developed a system called binomial nomenclature.

            a.         It involves giving each organism a two part name.

            b.         The names are in Latin so that no one language is favored.

            c.         This avoids the confusion caused by organisms with different common names in different areas.

            d.         The first part is the genus and the second part is the species.

                        i.         The genus name always starts with a capital letter.

                        ii.        The genus name can be abbreviated using the first letter of the name.

                        iii.       The species name always starts with a lower case letter.

            e.         The 2 part name gives clues about relationships between organisms.

            f.         Names were based largely on physical appearances but modern taxonomists use chromosomes, proteins, and they way organisms develop to help them classify species.(phylon, G - tribe; genesis, G - beginning)

6.         We now classify things into seven major categories

            a.         Kingdom

            b.         Phylum

            c.         Class

            d.         Order

            e.         Family

            f.         Genus

            g.         Species

7.         As you move down the seven levels of classification from kingdom to species, the species become more closely related.

Six Kingdoms

1.         Kingdoms are very general groups with broad characteristics

            a.         Kingdom Archaebacteria contains very ancient, simple bacteria.

                        i.         They can live in very harsh conditions such as very hot or acidic conditions.

            b.         Kingdom Eubacteria are more modern bacteria.

                        i.         They can be found in nearly every known habitat.

                        ii.        Some are consumers, some producers, and some decomposers.

                        iii.       Some cause disease but most are harmless.

            c.         Kingdom Protista

                        i.         Most are unicellular organisms.

                        ii.        Species are usually put in this kingdom if they don’t seem to fit anywhere else.

                        iii.       Some show characteristics of animals, some of fungi, and some of plants.

            d.         Kingdom Fungi

                        i.         Most fungi are multicellular but some are unicellular.

                        ii.        Most have cell walls made of a substance called chitin.

                        iii.       Fungi are heterotrophs. They get nutrients by absorbing it from the environment.

            e.         Kingdom Plantae

                        i.         Plants are all multicellular.

                        ii.        They are all producers.

                        iii.       Plants have a cell wall made of cellulose.

                        iv.       They have chlorophyll which is used to make sugar by photosynthesis.

            f.         Kingdom Animalia

                        i.         Animals are multicellular.

                        ii.        All animals are heterotrophs.

                        iii.       They are all motile.