THE SCIENCE OF BIOLOGY

Chapter OneSection 1-1

Scientific Thought Involves:

Questioning ideas-Scientists must be skeptical of new ideas. Rely on evidence not opinions

Discovery and change- Scientists must realize that new discoveries may change old ideas. Examples?

Universal laws are…

Definition of a universal law:A truth that scientist have found to be true everywhere in the universe.

-Law of gravity-Law of conservation of energy.

Science and Ethics

What does it mean to be ethical?-To have moral principles and values.

What are some ways that you would expect a scientist to be ethical?-Providing true and accurate data.-Not making false claims.-Not using involuntary subjects.-Obey laws.

Why study science?

Critical thinking skills.Better take care of your health, better

understanding of health.Wiser consumer.Better informed citizen.

Chapter 1Section 2

Scientific Method

Evidence Based on Observation

Observation-Using one or more senses to perceive objects and events.

Data-Information gathered from observation

(evidence).

The scientific method

A systematic approach to problems solving.

Can be used by anyone, even for non-scientific problems!

Step One

1. Make an OBSERVATION. Is the act of noting or perceiving objects or

events. Observations lead to a question or problem. Example: Some flowers grow taller than others.

I wonder if the amount of fertilizer changes the height?

Step Two

2. Form a HYPOTHESIS.

A hypothesis is a possible explanation to a problem that can be tested by

experiments.

Should be written in an “if…then” format

Testable- Must be able to collect data on the hypothesis (numbers, observations, make inferences).

Hypothesis

Example hypothesis:

If I apply 0 tsp, 1 tsp, 2 tsp and 3 tsp of fertilizer on the plants, then the beans with 2 tsp of fertilizer will grow the tallest.

Step Three

3. Conduct a controlled EXPERIMENT.

A procedure that is carried out under controlled conditions to test a hypothesis.

Control- is the standard for comparison. Usually the “normal” conditions.

Example- The control for the bean experiment would be the plant that received zero tsp. of fertilizer.

Step Three: EXPERIMENT

Constants- the parts of an experiment that stays the same for all trials.

Example: In the plant experiment the amount of light would have to remain constant for all of the plants being tested.

Step Three: EXPERIMENT

Independent variable: The factor that scientists change in the experiment.

Example: Amount of fertilizer.

Dependant variable: The factors that change in response to the independent variable. (What we are trying to observe).

Example: Height of the plants.

Step Four

ANALYZE RESULTS:Look at data collected, use it to accept

or reject the hypothesis.Example: In the plant you would look

at data to see which plants grew the tallest.

Step Five

5. Draw a CONCLUSION.

After you have analyzed data decide whether or not your hypothesis is accepted or rejected.

It’s OK if it is rejected!Example: The plant with 1 tsp. of

fertilizer grew the tallest, therefore our hypothesis is rejected.

Step Six

CONSIDER BIAS AND REPEATThink about reasons why the experiment may

have been bias.Example: Was the plant experiment funded

by an organic foods farm?Repeat the experiment to see if you get the

same results.May lead to a new hypothesis.

What are the steps of the scientific method?

1.2.3.4.5.6.

What is a Scientific Theory?

Theory= When a hypothesis is well supported and can be used to explain a broad range of data.

For example: The “Cell Theory” states that all living things are made up of cells.

Steps to Constructing a Theory

Chapter OneSection Three

Tools of Biology

How do scientist measure?

Using SI=the International System of Units otherwise known as the “metric system.”

Everything is scaled in multiples of 10 to make it easier to use.

Most of the world uses this system for measuring.

Common SI Units

Prefix Factor Volume Length Mass

Kilo- 1,000 1 kiloliter= 1,000 L

1 kilometer= 1,000 m

1 kilogram=1,000 g

1 1 liter (L)

1 meter (m)

1 gram (g)

Centi- 0.01 1 centiliter= 0.01 L

1 centimeter=0.01 m

1 centigram =0.01 g

Milli- 0.001 1 millimeter =0.001 L

1 millimeter=0.001 m

1 milligram =0.001 g

Lab Techniques

Microscopy-Using microscopes to magnify objects too small for the unaided eye.

Sterile techniques- A method to keep unwanted bacteria off of equipment.

Collecting data remotely- using tools such as GPS to track animals.

Sterile Technique

Parts of the microscope

Proper Way to Carry a Microscope

A Few Other Tools to Know:

Graduated Cylinder Erlenmeyer Flask

Lab Safety:

Follow verbal and written instructions EXACTLY.

Never touch broken glass.Keep purses, bags, extra books and other

clutter off of the lab tables.If there is any type of emergency remain calm

and tell your teacher immediately. Pay attention to what you are doing and do

not wander around the room.

Chapter OneSection Four

What is Biology

Biology is:

Biology is the study of ALL life.

Biology Includes:

Biochemistry-The study of chemistry in living things.

Ecology-The study of the environment.Microbiology-The study of microscopic living

things.Botany- The study of plants.Zoology-The study of animals.Anatomy-The study of body structure.

All Living Things have 7 Characteristics of Life

1. Cells- All living things are made of at least one cell.

2. Homeostasis-Maintain internal conditions.3. Metabolism- The sum of all chemical rxn in

the body. 4. Reproduction- All living things have the

ability to reproduce.5. Responsiveness- Respond to the

environment.6. Heredity- All living things can pass on DNA

to offspring.7. Growth- All living things grow and develop

with age.

1. Cells

Every living thing is made up of at least one cell:

2. Homeostasis

Homeostasis=When an organism maintains a stable internal environment.

3. Metabolism

Metabolism=Any chemical reaction that occurs in a living body. (All living things do this).

4. Responsiveness

All living things respond to their environment.

5. Reproduction

Reproduction=The process by which organisms make more of their own kind from one generation to the next.

6. Heredity

Heredity=When an organism passes on it’s traits to offspring through DNA.

All living things contain DNA in their cells.

7. Growth

All living things grow. Some for a short period of time and some for thousands of years like the sequoia.