Download Characteristics Of Life

Origin Statement – August
8, 2012
From your experience so far,
what do you know about science?
 Write down as much of the
scientific method, in order, as you
remember!

Chapter 1
Introduction: Themes
in the Study of Life
Science is:
A process
 A way of “knowing”
 A way of answering the questions
of science (and the world!)
 Based on:

◦ Observations (both qualitative and
quantitative)
◦ Experiments
◦ Deductive reasoning
Observations:
Are the “keystone” to science
 If it can’t be “observed”, it can’t
be studied by the Scientific
Method
 Can be made through your
senses or through the use of
tools

Scientific Method:
Outlines a series of steps for
answering questions.
 Obtains “evidence” through the use of
experiments.
 Use the scientific method when
answering your AP Bio Exam lab
questions!!!!

Scientific Method Steps
1. Identify the problem.
2. Identify what is already known
3. Formulate a hypothesis.
*Use “If…then…” format
4. Conduct an experiment.
Scientific Method Steps
5. Collect data.
6.Compare data to hypothesis.
7. Conclusions and new
hypothesis.
Comment…

Nothing is ever proven in
science
◦ Can only be disproven


Experiments either support
or fail to support a particular
hypothesis
Disproving a hypothesis is as
important as supporting it –
why?
Theories vs. Hypotheses
Theories are broader in scope
than hypotheses
 Not determined by single
experiment, but have been
supported by many experiments
by many scientists
 Comprehensive explanation
supported by abundance of
evidence
 Theories allow predictions

Examples of Theories
Atomic Theory
 Gravitational Theory
 Theory of Relativity
 Cell Theory
 Theory of Evolution by Natural
Selection

4 AP Biology “Big Ideas”
The process of evolution drives the
diversity and unity of life.
2. Biological systems utilize free energy
and molecular building blocks to grow,
to reproduce, and to maintain
dynamic homeostasis.
3. Living systems store, retrieve,
transmit, and respond to information
essential to life processes.
4. Biological systems interact, and these
systems and their interactions possess
complex properties.
1.
Side Note about Big Idea #1

“Nothing in Biology makes sense
except in the light of Evolution.”
◦ Theodosius Dobzhansky
 American Biology Teacher 35:125-129, 1973.

Success is measured by an
organism’s ability to:
◦ Survive
◦ Reproduce


Note – organisms survive because
of their adaptations, they do not
adapt to survive.
Note – individual organisms do not
evolve, populations do.
Properties of Life
1.
2.
3.
4.
5.
6.
7.
8.
9.
Order
Reproduction
Growth and Development
Use of Energy
Respond to environment
Homeostasis
Evolution
Cellular make-up
Death
1. Order



Living things are highly organized
in structure and function.
Analyzing a biological structure
gives us clues about what it does
and how it works
Structure and function are related
at all organizational levels
(organelle, cell, tissue etc.)
2. Reproduction
Organisms reproduce their own
kind.
 Life on Earth uses the nucleic
acid and the genetic code for
heritable information.

3. Growth &
Development
Organisms increase in size and
complexity.
 Growth - increase in size.
 Development - increase in
complexity.
 Life - grows by internal changes
(often at the cellular level).

4. Energy Utilization
Organisms take in energy and
transform it to do work.
 Organisms are “open” systems;
they must continually take in
energy.

5. Response To
Environment
Organisms respond to changes or
stimuli in their environment.
 The speed of the response may
be “fast” or “slow”.

6. Homeostasis
Organisms maintain their internal
environment within tolerable
limits.
 “homeo” = same “stasis” = state

7. Evolutionary
Adaptation
Organisms change over time as
they adapt to their environment.
 Organisms must adapt, move, or
die!

Others
8. The cell is the “basic unit” of
life.
9. ALL organisms die.
Summary






Recognize the use of “Big Ideas” in the
study of Biology.
Identify the general and specific
properties of life.
Recognize that the study of life does
not make sense without evolution.
Appreciate that science is a process.
Recognize and use the steps of the
scientific method.
Differentiate between a hypothesis and
a theory.