The Organization of Life

How do we organize living things?

Branches of biologyO Because biology is so vast, it is

divided into many smaller sub-fields of study.

O Many of these areas of study focus on certain divisions of the natural world.

MoleculesO These are

clusters or groups of atoms.

O Smallest unit of any compound.

CellsO These are the

smallest units of life.

O Contain several different molecules.

Groups of cellsO These are

structures that are made up of cells.

O We will cover this in later units.

OrganismsO One individual

living thing.O May be

unicellular or multicellular.

O Includes you and me!

PopulationO A group of ONE

specific organism.

O For instance, a flock of geese is a population.

CommunityO ALL of the

populations within a given area.

O All populations within a community interact with one another.

EcosystemO A single

community, combined with all of the non-living factors in the area.

O Includes rocks, water, air.

O Non-living factors are abiotic. (“not living”)

O Living factors, such as a population, are biotic (“living”.

BiosphereO All of the

ecosystems on Earth.

O Biosphere means “living sphere”.