Classifying Living Things

overhead

There are over one and a half million species of living things, with the possibility of millions more to be discovered. To study and collect information on so many different species, scientists began grouping or classifying the organisms on the basis of common characteristics.

Scientists have struggled to find correct classification systems to use. Early classification systems grouped things by whether they were alive or not. Then scientists divided all organisms into two kingdoms:  plants and animals. Finally, they realized that there were significant differences between specific types of plants and animals. A more recent classification scheme divides all organisms into five kingdoms: animals, plants, fungi, monerans, and protists. We will look at the first three of these.  Classification schemes are human inventions.

By grouping things systematically, we avoid confusion and make it easier to work with things.

There is often more than one way to group things so that they can be easily found or recognized.

By knowing something about one member of a group, a person may know something useful about other members of the group.

Questions to answer

Characteristics of Living Things

It is not always an easy thing to tell the difference between living, dead, and non-living things. Prior to the 1600's many people believed that nonliving things could spontaneously turn into living things. For example, it was believed that piles of straw could turn into mice. That is obviously not the case. There are some very general rules to follow when trying to decide if something is living, dead, or non-living. Listed here are the six rules used by scientists:

If something follows one or just a few of the rules listed above, it does not necessarily mean that it is living. To be considered alive, an object must exhibit all of the characteristics of living things. Sugar crystals growing on the bottom of a syrup container is a good example of a nonliving object that displays at least one criteria for living organisms

You can take a Living vs Non-Living quiz here: http://utahscience.oremjr.alpine.k12.ut.us/sciber00/7th/classify/living/quiz/livingqu.htm
Classification of Animals powerpoint, good review and quiz
http://www.teachingandlearningresources.co.uk/classification.ppt

http://www.teachingandlearningresources.co.uk/classification01.shtml    adapted for lesson

A Touch of Class sorting game www.sciencenetlinks.com/interactives/class.html

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