Levels of Biological
Organization
In your journal start with the biosphere and list the levels of
life down to an atom.
Play the game!
• Levels of Life Card Game…
• http://www.ldsd.org/Page/1436
Biosphere
• All of the life on
earth and all of the
places where life
exists
Ecosystem (and Biomes)
• Consists of all the
living things in a
particular area, along
with all the nonliving
components of the
environment with
which life interacts,
such as soil, water,
atmospheric gases,
and light
• Biome – any of the
world’s major
ecosystems
Community
• All of the living
organisms inhabiting
a particular area
Population
• Consists of all the
individuals of a
species living within
the bounds of a
specified area
Organism
• An individual living
thing
Organ System
• A group of organs
that cooperate in to
carry out a particular
function for the
organism
Organ
• A body part that
carries out a
particular function in
the body
Tissue
• A group of cells that
work together to
preform a specialized
function
Cells
• Life’s fundamental
unit of structure and
function
• unicellular
• multicellular
Organelles
• Functional
components within a
cell
Molecules and Atoms
• Molecule - A chemical structure consisting of
two or more small chemical units called atoms
• Atom – the smallest unit of matter that retains
the chemical properties of an element
So what do all of these levels of
life allow for....
• Emergent Properties
– due to the
arrangement and
interactions of parts
as complexity
increases an
organisms is capable
of specialized
functions (i.e.
oxidative
phosphorylation)
Does emergence only stop at
the organism level?
• No –populations can
work together to
carryout complex
activities – think of a
colony of Ants;
emergent properties
are present at all
levels of life
Reductionism vs. Systems
• Reductionism Reducing complex
systems to simpler
components that are
more manageable to
study
Reductionism could allow for the
discovery of a drug that lowers blood
pressure – Systems biology would make
sure that the drug did not have an
adverse affect on the rest of the body.
• Systems Biology –
attempts to model
the dynamic
behavior of whole
biological systems
based on a study of
the interactions
among the system’s
parts