Transcript What is Life?

Chapter 1
Scientific Process and
Themes of Biology
1-3 Scientific Process
Scientific
knowledge is
acquired using a rigorous
process
True science always follows
this process
Don’t be fooled by
pseudoscience!
Steps to Process
Collecting
observations
Asking questions
Forming hypotheses and
making predictions
Confirming predictions
Drawing conclusions
Observations
Using
your senses, observe
the world around you
Document your observations
Asking Questions
Ask
questions based on your
observations
What was causing your
observation?
Forming Hypotheses and
Predictions
Hypothesis-a
statement that
can be tested by more
observations or
experimentation
Prediction-expected outcome
of a test
Confirming Predictions
Use
a controlled experiment
(must have certain key parts)
Control Group-group in an
experiment that receives no
experimental treatment
Independent
Variable-the
factor that is varied in the
experiment
Dependent Variable-variable
that is measured in the
experiment
Drawing Conclusions
Was
the hypothesis
supported or rejected?
Why did the data support or
reject the hypothesis?
Publishing Results
Most
experiments are
eventually published
Accumulation of related
hypotheses that have been
tested many times by many
scientists can result in a
theory
1-1 Themes of Biology
Biology
is the study of life
There are 7 properties of life
Cellular
Organization
Reproduction
Metabolism
Homeostasis
Heredity
Responsiveness
Growth and Development
The
science of Biology is
unified by 7 distinct themes
These are different then the 7
properties of life!
Unifying Themes of Biology
(1)Cellular
Structure-all living
things are made of one or
more cells
(2)Reproduction-all living
things must reproduce
(3)Metabolism-the sum of all
chemical rxns carried out
inside an organism
 (4)Homeostasis-maintaining
a
stable environment inside of the
cell
 (5)Heredity-passing characteristics
from parents to offspring
 Gene-set of inherited instructions
for making proteins
 Mutation-change in the DNA of a
gene
 (6)Evolution-change
in the
inherited traits of species over
time
 Species-group of genetically
similar organisms that can
produce fertile offspring
 Natural Selection-organisms with
favorable genes are more likely
to survive and reproduce
(7)Interdependence-
organisms have evolved to
interact with other organisms
Ecology-the science that
studies the interactions of
living organisms with the
nonliving part of their
environment