1. Chapter 1 “The Science of Biology”
The goal of science is to investigate and understand, to explain events in nature, and to use those explanations to make useful predictions.

2. Chapter 1 – 1 “What is Science?”
Science – an organized way of using evidence to learn about the natural world
Science only deals with the natural world
Scientists collect and organize data looking for patterns and connections between events
Scientists propose explanations that can be tested through experimentation

3. What is Science? Science always starts with an observation
Scientists observe the natural world using all of the five senses of the body as they gather information
The evidence that scientists gather from their observations is called data

4. Scientific Observation
Observations can be classified into two types:
Quantitative observations involve numbers, counting, or measuring objects
(Example) How many Basenjis have destroyed the pillow?
Qualitative observations involve things that cannot be easily measured like color or texture
(example) One of the basenjis has a white “ring” around it’s neck

5. What is Science? Interpreting Evidence
After a scientist gathers evidence or observes something they must be able to interpret the evidence or data
This means that they need to try and understand what was observed
This is usually done with an inference
A logical interpretation based on prior knowledge and experience

6. What is Science? Explaining the Evidence
Scientists form hypotheses to provide possible explanations for the natural world
A Hypothesis is a possible explanation for a set of observations or an answer to a scientific question
DO NOT write: an educated guess!!!
In science, a hypothesis is useful only if it can be tested

7. Designing an Experiment
State the Problem
Analyze Results
Form a Hypothesis
Draw a Conclusion
Make Predictions
Publish Results
Set up Experiment

8. Designing an Experiment
Experiments are the difference between ideas and reality!
Before experiments, ideas like spontaneous generation were accepted
The idea that life arose from non-living matter

9. Controlled Experiments
When you test a hypothesis in science you must design an experiment
The factors that you change in the experiment are called variables
Variables can be a number of things:
Equipment
Type of material
Amount of material
Temperature
Light
Time

10. Controlled Experiments
A controlled experiment is when you are able to test only one variable at a time
Whenever possible, this is the best type of experiment
This is also called “isolating the variable”
All of the other variables remain constant or controlled
Manipulated variable – the variable that is deliberately changed
Responding variable – the variable that changes can be observed as a response to the manipulated variable

11. Redi’s Experiment on Spontaneous Generation
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
Manipulated Variables:
gauze covering that
keeps flies away from
meat
Several
days pass
Responding Variable:
whether maggots
appear
No maggots appear
Maggots appear
CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous generation of maggots did not occur.

12. Section 3 “Studying Life”
BIOLOGY means “the study of life”
In order to be considered part of biology something must have these “characteristics of living things”:
Living Things:
Are made up of units called cells
Are able to reproduce
Are based on a universal genetic code (DNA)
Are able to grow and develop
Obtain and use materials and energy
Respond to their environment
Maintain a stable internal environment
As a group, change over time

13. Section 3 “Studying Life”
Being Made up of Cells :
A cell is a collection of living matter enclosed by a barrier that separates the cell from it’s surroundings
Cells can grow in response to their environment and they can be quite complex even though most cells are very small
Many living things are made up of only one cell and are called unicellular meaning “single celled”
When an organism is made up of many cells it is called multicellular
Our bodies are multicellular, highly complex living organisms

14. Section 3 “Studying Life”
All Living things must Reproduce :
Whenever an organism creates another organism it is called reproduction
There are two types of Reproduction:
Sexual Reproduction is when two parents contribute a cell to create a new organism
Asexual Reproduction is when one parent can create a new organism either by dividing in half or breaking off a piece of itself to contribute to a new organism

15. Section 3 “Studying Life”
Based on a Genetic Code:
When one organism produces offspring as in asexual reproduction, the offspring are genetically identical
Sexual reproduction involves the genes from two parents and yields offspring that are genetically unique
Any way an organism is created they are all similar in one way, the fact that they are made up by a molecule called DNA (Deoxyribonucleic Acid)
DNA consists of four nitrogen bases and it is the arrangement, order, and number of these bases that code for every living organism on our planet

16. Section 3 “Studying Life”
Living things Grow and Develop :
During the life of an organism it grows and develops in it’s environment
Living things Obtain and Use Materials and Energy :
All living things must consume whether or not they are a plant, animal, fungus, or bacteria
An organism’s metabolism is a combination of chemical reactions that break down food and materials
Living things respond to their environment :
A stimulus is a signal to which an organism responds like a light or a sound

17. Section 3 “Studying Life”
Levels of Organization:
Our planet is extremely diverse in population and we can organize based on a system called levels of organization
The Biosphere is the part of the earth that contains all of the ecosystems
An ecosystem is the community and it’s non-living surroundings
A community is a population that lives in a defined area or space