CLASSIFICATION of living things by ajizai



                                  Why do we classify things?

* Classification provides scientists and students a way to sort and group organisms for easier
* There are millions of organisms on the earth! (approximately 1.5 million have been already

Organisms are classified by their:
* physical structure (how they look)
* evolutionary relationships
* embryonic similarities (embryos)
* genetic similarities (DNA)
* biochemical similarities

                                    UNITY AND DIVERSITY

All living things carry out the life functions. There are many different types of organisms.

 In one classification system, there are 2 main groups. In others, there are 3. In the one used
  by most of the world's scientists, which we will also use, there are 5 main groups. All living
things are placed in one of the five KINGDOMS...which are the most general group. They are
then broken down into smaller groups, then smaller groups, then smaller and so on until there
                       is just one... SPECIES is the most specific group...
Can you make a sentence using the first letter of each classification subgroup?
* TAXONOMY--the branch of science that classifies and names living things.

* NOMENCLATURE--a system for naming things

      In biology there is a two-word system that is used to name organisms. It is called
               BINOMIAL NOMENCLATURE (a two named--naming system).

    Carolus Linnaeus devised this in the 1800's using these two subgroups for the name:

                                  GENUS & SPECIES
                               (more general) (more specific)

* Humans are known as Homo sapiens

                                     The Five Kingdoms


              Can you make a sentence using the first letter of each kingdom?
Organisms are groups among these five kingdoms by:
* the presence or absence of a nuclear membrane
* unicellular (one cell) or multicellular (many cells)
* the type of nutrition used by the organism (heterotrophic or autotrophic)
We will also go into the main phyla (next subgroup) for each kingdom.

I. Kingdom MONERA--
* have a primitive cell structure lacking a nuclear membrane--PROKARYOTE
* most of this kingdom are unicellular (some exist in multicellular clusters)
* two main phyla

A) Bacteria (heterotrophic)
B) Blue-green algae (autotrophic)
II. Kingdom PROTISTA--
* has a membrane around the nucleus of the cell--EUKARYOTIC
* predominantly unicellular
* two main phyla

A) Protozoa--animal like nutrition (heterotrophic)

ex. paramecia, ameba

B) Algae--plant like nutrition (autotrophic)

ex. spirogyra

III. Kingdom FUNGI--
* has a membrane around the nucleus of the cell--EUKARYOTIC
* absorbs food from its environment (heterotrophic), does NOT ingest it!
* organized into branched, multinucleated filaments

ex. bread molds (multicellular)
mushrooms (multicellular)
yeast (unicellular)
IV. Kingdom PLANTS--
* has a membrane around the nucleus of the cell--EUKARYOTIC
* multicellular organisms
* photosynthetic organisms (autotrophic)

                              (photo=light) (synthesis=to make)


V. Kingdom ANIMAL--
* largest of 5 kingdoms
* has a membrane around the nucleus of the cell--EUKARYOTIC
* multicellular
* ingests their food (heterotrophic)
* four main phyla

A) Coelenterates (soul-en-ter-ates)

1) has only two layers of cells
2) has a hollow body cavity
ex. hydra, jellyfish

B) Annelids

1) has segmented body walls (rings)
ex. earthworm, sandworm

C) Arthropods

1) has an exoskeleton (exo=outside)
2) has jointed appendages
ex. grasshopper, lobster, spiders, insects

D) Chordates

1) have a dorsal (back) nerve cord
2) have an endoskeleton (endo=inside)
ex. sharks, frogs, humans, cats

                   **Chordates have many CLASSES (the next subgroup)**
                                      Pisces (ex. fish)
                                   Amphibians (ex. frogs)
                                    Reptiles (ex. lizards)
                                      Aves (ex. birds)
                         Mammalia (ex. humans, cats, dogs, whales)

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