1. Chapter 1
The Science of Biology

2. Section Outline
Section 1-1
1–1 What Is Science?
A. Science is an organized way of using evidence to learn about the world.
B. The goal of science is to investigate and understand the natural world, explain events in the natural world, and make useful predictions.
C.Science is a body of knowledge that has been built up by scientists after centuries of using the scientific method.(We stand upon the shoulders of giants-Isaac Newton)

3. 1-2 How Scientists Work
Scientific Method
Observation- Gather information (data; Quantitative & Qualitative) about something in an orderly way and ask a question
Form a hypothesis- a proposed scientific explanation for a set of observations; a testable educated guess
Controlled Experiment- includes variables (factors that change)
a. Manipulated Variable (Independent)- variable that is deliberately changed
b. Responding Variable (Dependent)- variable that is observed and changes in response to the manipulated variable
c. Controlled Variable (Control)- variable that is kept the same for use as a comparison
d. In a good experiment, only one variable is manipulated at a time.

4. 1-2 How Scientists Work
Scientific Method continued
Recording and Analyzing Results- collecting data (information obtained from experiments)
a. In science, we must be able to replicate our experiments. Recording our process and data accurately is a must.
b. By recording our data we are able to build upon past knowledge
Drawing a Conclusion- using the evidence to validate or refute the hypothesis.
Sometimes it is a good thing to be wrong! Every experience is a learning experience!

5. Flowchart Flow Chart “Designing an Experiment” State the Problem
Section 1-2
Flow Chart “Designing an Experiment”
State the Problem
Analyze Results
Form a Hypothesis
Draw a Conclusion
Set Up a Controlled Experiment
Publish Results
Record Results

6. 1-2 How Scientists Work
Theory- a well tested explanation that unifies a broad range of observations. Sometimes a particular hypothesis becomes so supported from numerous investigations scientists consider it a theory.

7. Figure 1-8 Redi’s Experiment on Spontaneous Generation
Section 1-2
OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat.
HYPOTHESIS: Flies produce maggots.
PROCEDURE
Uncovered jars
Covered jars
Controlled Variables:
jars, type of meat,
location, temperature,
time
Several
days pass
Manipulated Variables:
gauze covering that
keeps flies away from
meat
Responding Variable:
whether maggots
appear
Maggots appear
No maggots appear
CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous generation of maggots did not occur.

8. Figure 1-10 Spallanzani’s Experiment
Section 1-2
Gravy is boiled.
Flask is
open.
Gravy is teeming
with microorganisms.
Flask is
sealed.
Gravy is free of
microorganisms.
Gravy is boiled.

9. Figure 1-11 Pasteur’s Experiment
Section 1-2
Broth is boiled.
Broth is free of
microorganisms
for a year.
Curved neck
is removed.
Broth is
teeming with microorganisms.

10. 1-3 Studying Life Characteristics of Living Things
1. Made Up of Cells- smallest unit of an organism considered alive
Reproduction- producing new organisms
a. Sexual- cells from two different parents unite
b. Asexual- new organism comes from only one parent
3. Based on a Genetic Code- directions for life processes come from DNA
4. Growth and Development
5. Need for Materials and Energy- metabolism is the combination of chemical reactions happening in your body
6. Response to the Environment- A stimulus is a signal to which an organism responds. A reaction to a stimulus is called a response.
7. Maintaining Internal Balance (homeostasis)
8. Evolution- change over time

11. Characteristics of Living Things
Section 1-3
Characteristic
Examples
Living things are made up of units called cells.
Many microorganisms consist of only a single cell. Animals and trees are multicellular.
Living things reproduce.
Maple trees reproduce sexually. A hydra can reproduce asexually by budding.
Living things are based on a universal genetic code.
Flies produce flies. Dogs produce dogs. Seeds from maple trees produce maple trees.
Living things grow and develop.
Flies begin life as eggs, then become maggots, and then become adult flies.
Living things obtain and use materials and energy.
Plants obtain their energy from sunlight. Animals obtain their energy from the food they eat.
Living things respond to their environment.
Leaves and stems of plants grow toward light.
Living things maintain a stable internal environment.
Despite changes in the temperature of the environment, a robin maintains a constant body temperature.
Taken as a group, living things change over time.
Plants that live in the desert survive because they have become adapted to the conditions of the desert.

12. Figure 1-21 Levels of Organization
Section 1-3
Biosphere
The part of Earth
that contains all
ecosystems
Biosphere
Ecosystem
Community and
its nonliving
surroundings
Hawk, snake, bison, prairie dog, grass, stream, rocks, air
Community
Populations that
live together in a
defined area
Hawk, snake, bison, prairie dog, grass
Population
Group of
organisms of one
type that live in
the same area
Bison herd

13. Figure 1-21 Levels of Organization continued
Section 1-3
Organism
Individual living
thing
Bison
Tissues, organs,
and organ systems
Groups of
Cells
Nervous tissue
Brain
Nervous system
Smallest functional
unit of life
Cells
Nerve cell
Groups of atoms;
smallest unit of
most chemical
compounds
Molecules
Water
DNA

14. 1–4 Tools and Procedures Section Outline A Common Measurement System-
Metric System- decimal system of measurement whose units are based on multiples of 10
2. Microscopes (we will learn more in Chapter 7)
1. Compound Light Microscopes- allow light to pass through the specimen and use two lenses
2. Electron Microscopes- use electrons to produce images of specimens (images are1000 times more detailed than light microscope)
D. Laboratory Techniques
1. Cell Cultures- cells are reproduced so they can be studied
2. Cell Fractionation- cells are broken up and the parts are separated for studying individual cell parts.

15. Click a hyperlink to choose a video. It’s Alive!, Part 1
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It’s Alive!, Part 1
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