More Classification Notes



Key physical features and activities are how organisms are classified.


Carolus Linnaeus created today’s classification system.


The Three Domain System, developed by Carl Woese, is a system for classifying biological organisms. 


The Three Domains are : Archaea, Bacteria, and Eukarya.  The current system, the Three Domain System, groups organisms primarily based on differences in ribosomal RNA structure. Ribosomal RNA is a molecular building block for ribosomes.


RNA stands for ribonucleic acid which is a nucleic acid that plays an important role in the production of proteins.

Ribosomes are: tiny structures in the cytoplasm of a cell where proteins are made.


Prokaryotes are: organisms whose cells lack a nucleus and some other cell structures


Eukaryotes are: organisms with cells that contain nuclei and other cell structures


The 8 levels of classification from very general/biggest to specific/smallest are:


1. Domain

2. Kingdom

3. Phylum

4. Class

5. Order

6. Family

7. Genus

8. Species


There are 6 kingdoms, but as new data is collected and discoveries are made the number can change.  These are the current kingdoms:


1. Animal

2. Plant

3. Archaebacteria

4. Eubacteria

5. Protist

6, Fungus


An Autotroph can make its own food


A Heterotroph cannot make its own food


An organism’s binomial nomenclature is the naming system which includes its genus and species.

Genus is capitalized and listed first and species is lower case and listed second.  The name should be written in italics.














Pro or Euk

(cell type)







Auto or Hetero



Can be both


Can be both


Can be both







Uni or Multi

(#of cells)




some are uni

Multicellular, some are uni



A species is a group of similar looking organisms that can mate with each other and can reproduce fertile offspring.  A mule is not a species because they are born sterile and therefore cannot reproduce.


A vertebrate is: an animal with a backbone


An invertebrate is: an animal without a backbone


Carnivores eat: meat

Herbivores eat: plants

Omnivores eat: both meat and plants


Major Animal Phyla are:



Which are? Animals that have stinging cells and take their food into a hollow central cavity


Examples include: jellyfish, anemones, hydras, coral reefs-are built by cnidarians



Which are? Invertebrates with soft, un-segmented bodies that are often protected by hard outer shells and have a thin layer of tissue called a mantle, which covers their internal organs


Three main groups: gastropods, bivalves, and cephalopods


Examples include: snails, slugs, clam, oysters octopus and nautiluses



Which are? Invertebrates, and they all have long, narrow bodies without legs and have head and tail ends


The three types are: flatworms, roundworms, and segmented worms



Which are? Invertebrates that has an external skeleton, a segmented body, and jointed attachments called appendages


Five main groups: crustaceans, arachnids, centipedes, millipedes, and insects


Examples include: crab, crayfish, shrimp, spiders, scorpions, ticks, grasshopper, butterfly, bee



Which are? Five-part radial symmetry and an endoskeleton, echinoderms also have an internal fluid system called a water vascular system


Examples include:  sea stars, sea cucumbers, sea urchins, sand dollars, brittle stars



Which are? at some point in their lives, they have a notochord, a nerve cord, and slits in their throat area

The five main groups are: fish, mammals, birds, amphibians, reptiles


Examples include: trout, sharks, whales, cows, cardinals, hawks, frogs, snakes


Symmetry is having balanced portions

The two types of symmetry are

1. bilateral –split in two, mirror images.  Butterflies

2.radial–lines of symmetry that go from a central part.  Sea anemones


Major Plant groups/divisions/phyla are


Nonvascular plants

Examples include: mosses, liverworts and hornworts



vascular and reproduce through spores

Examples include: Ferns, club mosses, and horsetails



Are seed plants, also called gymnosperms

Examples include: spruce, pine, hemlock


Found in old textbook in Chapter 9


Flowering Plants

Are seed plants, also called angiosperms

Examples include-grasses, lilies, apple trees and maple trees


In the sporophyte stage in the life cycle of a plant, the plant produces spores for reproduction.


In the gametophyte stage in the life cycle of a plant, the plant produces gametes, or sex cells.


A nonvascular plant is a low-growing plant that lacks vascular tissue.


A vascular plant is a plant that has vascular tissue.



The smallest/basic unit of life is the cell.

All cells come from other cells.

All living things are made up of cells.

From smallest to most complex:

cell                                         tissue                                      organ                                     organ system



Photosynthesis is: The process by which plants and some other organisms capture light energy and use it to make food from carbon dioxide and water.

The raw materials of photosynthesis are: water and carbon dioxide

The products of photosynthesis are: sugar/glucose and oxygen


The chemical equation for photosynthesis is:


The organelle where plants make their food is the chloroplasts

Photosynthesis, plants, producers all make up the base of what? Food chains, food webs



What is a food chain? A series of events in which one organism eats another.

Overlapping food chains is called a food web.


Food chains/food webs have three basic roles: producer, consumer and decomposer.


Two examples of a producer would be: plant, autotroph, grass, trees

Two examples of a consumer would be: animal, human, cow, lion

Two examples of a decomposer would be: some bacteria, fungus

A predator is a carnivore that hunts and kills other animals for food and has adaptations that help it capture the animals it preys upon.

A prey is an animal that a predator feeds upon.

A parasite is an organism that lives on or in a host and causes harm to the host.

A host is an organism that provides a source of energy or a suitable environment for a virus or for another organism to live.


A group of closely related animals that work together for the benefit of the whole group is a society.


What are the benefits from living in a society?

Protection from predators, cooperation, finding mates




There are three cycles that are important in life science they are the water cycle, nitrogen cycle and the carbon cycle.  We are dependent on water, carbon, oxygen and nitrogen for all aspects of life processes.


Condensation is the gas state of water molecules going to a liquid state.


Evaporation is the liquid state of water molecules going to a gas state.


The forms of water that fall from the sky such as snow, rain, sleet and hail is called precipitation.


In the nitrogen cycle, nitrogen moves from the air to the soil, into living things, and back into the air.

In the carbon cycle, animals give off carbon dioxide which is in turn used by plants.  Plants give animals oxygen and the cycle starts all over again.