Levels of Organization in Biology1
1. This figure shows examples of the levels of organization for an African savanna ecosystem.
Fill in the blanks on the right to give examples for a population of frogs living in a pond.
Biosphere
All living things on
earth and the parts of
the earth they inhabit
Examples for a population of
frogs living in a pond
Ecosystem
All the living and
nonliving things in the
same environment __________________________
Community
All the populations in
a particular area
__________________________
Population
Organisms of the
same kind that live in
a particular area
__________________________
Organism
An individual
living thing __________________________
Organ – A structure
with multiple tissues
that work together to
do a particular task
__________________________
Tissue – A group of
cells with a similar
structure and function __________________________
Cell
Smallest unit
that is alive __________________________
Molecule
Smallest unit of a compound
that still has the properties of
the compound __________________________
Atom
The smallest unit of a
chemical element
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By Dr. Ingrid Waldron, Department of Biology, University of Pennsylvania, and Bradley String, Ridley High School, © 2020. This Student
Handout, a PowerPoint presentation, and Teacher Notes with suggested questions and points to include in the PowerPoint presentation are
available at https://serendipstudio.org/exchange/bioactivities/LevelsOrganization.
2. The figure in question 1 states that a cell is the smallest unit that is alive. List three
characteristics of life that cells have and molecules like water and oxygen do not have.
3a. An amoeba is a tiny single cell organism.
This figure shows some of the structures in
an amoeba. If a scientist took all the
molecules in an amoeba and mixed these
molecules in a test tube, do you think that
this mixture of molecules would be alive?
yes ___ no ___
3b. Explain your reasoning.
In this figure, the labels indicate the Brain
heart and the locations of small blood Wing muscles
vessels where molecules like oxygen can
enter or leave the blood.
4. Explain how the parts of the
circulatory system work together to help
the bird fly.
Heart Leg muscles
5. Give an example to illustrate how a property or ability is only observed at a larger level of
biological organization, and not observed in the component parts.
6. Give an example to illustrate how scientists can better understand a complex system by
studying its smaller component parts.
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7. Match each item in the list on the left with the best match from the list on the right.
_____ Biosphere A. All living things on earth and the parts of the earth they inhabit
_____ Cell B. A group of atoms bonded together
_____ Community C. A group of one kind of organism living in an area
_____ Ecosystem D. A group of similar cells working together
_____ Molecule E. Populations of different types of organisms living together
_____ Organ F. A living individual which contains one or more cells
_____ Organ System G. A structure with several tissues that work together to
accomplish a function
_____ Organelle H. All the living and nonliving things in the same environment
_____ Organism I. Parts of a cell such as the nucleus
_____ Population J. A group of organs working together
_____ Tissue K. Smallest level at which life exists
8. In the first column below, put the levels of organization listed above in order from smallest to
largest. Then, give examples of each level of organization for an amoeba population living in a
pond. Use a dash (–) to indicate each level of organization that is not observed in an amoeba.
Level of Organization Examples for an Amoeba Population Living in a Pond
Smallest:
Largest:
