Why
do we classify things?
* Classification
provides scientists and students a way to sort and group organisms for
easier study.
* There are millions of organisms on the earth! (approximately 1.5 million
have been already named)
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...

K
P C O F G S
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
MONERA
PROTISTA
FUNGI
PLANT
ANIMAL
M
P F P A
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
IV.
Kingdom PLANTS--
* has a membrane around the nucleus of the cell--EUKARYOTIC
* multicellular organisms
* photosynthetic organisms (autotrophic)
(photo=light)
(synthesis=to make)
PHOTOSYNTHESIS=TO
MAKE FROM LIGHT
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
1)
has segmented body walls (rings)
ex. earthworm, sandworm
1)
has an exoskeleton (exo=outside)
2) has jointed appendages
ex. grasshopper, lobster, spiders, insects
1)
have a dorsal (back) nerve cord
2) have an endoskeleton (endo=inside)
ex. sharks, frogs, humans, cats