Did we explain well enough what "levels of
organization" means? Think about your school, as an
example. Its levels of organization can include:
library, offices, gym, lunchroom, etc.)
board, superintendent, principal)
learning, sports, club meetings, etc.)
Living and the Dead
wonder what makes the difference between being dead and alive? To be
alive you have to be well organized - or at least your cells do.
the pictures of water or the rocks ... dead, right? Water only has
one kind of
in it, and these molecules are randomly moving around - not very
well organized. Rocks may have several kinds of molecules
that are locked into position by simple interactions with each other.
However, these molecules don't really DO anything.
things don't have to do anything.
Cells have to DO
many functions in order to stay alive.
To DO so can
require correct operations at many levels of organization
|Normal function of cells depends on
normal function of the many structures inside cells that help cells survive.
These structures are called "organelles" ("little organs").
When our cells are
healthy, we are healthy. When our cells are sick, we are sick. Sick
cells reflect disease.
of a cell, which has many parts called organelles
Organelles that are damaged or diseased
cannot perform their roles properly.
- Cells do not work as well as they get
- Cells are damaged by disease and
"wear and tear" of living.
- Many cells die, even without disease
(example: "shedding" of skin).
- Big problems can result when cells do
not replace themselves as they die (example: skin gets thinner and
more easily damaged in old age; death of neurons can cause senility,
Parkinson's disease, paralysis).
- Big problems result if cells replace
themselves in an out-of-control way (example: cancer).
Why It Matters |
How We Find Out |
What We Know
Self-Study Game |
Teachers Pages |
Peer Curriculum |
Cell Biology Home Page |
Copyright © 2001-2003
Web Site Privacy Statement