Chapter 1

The Science of

Biology

Chapter Vocabulary Lists

• You will keep a vocabulary list for every chapter in your notebook.

• My suggestion Use a section of your notebook to write all of the Chapter Vocabulary Terms.

• They will be easy to find all in one place.

1-1: What is Science?• asking questions about

the world around us is part of human nature– examples: how did life

begin? where did plants and animals come from?

– different cultures have different answers to these questions

Science• Organized process

whose goal is to investigate and understand the natural world

• Explain events in the natural world to make useful predictions

Biology is the study of living things.

Science is an ongoing process

• The most effective way to learn science or biology is to think like a scientist or biologist.

• observation – the process of gathering information about events or processes in a careful, orderly way.– sight and hearing

• Information we gather from observations is called data.

1-2: How Scientists Work• systematic approach to problem solving that

involves observation and experimentation• distinguishes a science from a nonscience• FIVE STEPS

1. Ask a question: observing and stating a problem2. Forming a hypothesis: possible explanation or

conclusion about some event in nature3. Testing the hypothesis with an experiment: or

controlled test4. Recording and analyzing data: recorded observations

and information5. Forming a conclusion Experiments must be able to be replicated.

Thinking like a scientist• We use data to make inferences – logical

interpretations based on prior knowledge or experience.

• A hypothesis is a proposed scientific explanation for a set of observations.

Always must be based in science.

A Controlled Experiment • variable: single factor that is isolated and tested in an

experiment– can only be ONE variable

• constant: the part of the experiment that stays the same from setup to setup

• control setup: part of the experiment that does not contain the variable

• experimental setup: part of the experiment that contains the variable being tested

• controlled experiments allow researchers to isolate and test the effects of a single factor

Types of Data

• Write working definitions for each type of data.

• Quantitative

• Qualitative

Identifying Variables

• In a controlled experiment, only ONE variable is tested at a time.

• Manipulating variable is the variable that is deliberately changed.

• Also called the Independent variable.

• Responding variable is the variable that is observed. It changes in response to the manipulated variable.

• Also known as the dependent variable.

Theory

• A well-tested explanation that unifies a broad range of observations.

• Make accurate predictions about new situations.

Spontaneous Generation

• Idea that life could arise from nonliving matter• Redi’s Experiment on Spontaneous

Generation

Redi’s Experiment

• Controls that remain the same:– Jars, type of meat, location, temperature

• Manipulated Variables:– Gauze covering the jars

• Responding Variables:– Whether maggots appear

Reproducing Results

Spallanzani’s Test

Spallanzani’s Test

• Controls:– Type of flask, location, heat, chicken broth

• Manipulated Variables:– Cork used to stopper flask

• Responding Variables:– Presence of microorganisms in broth

Pasteur’s Experiment

• Read through Pasteur’s experiment in your textbook.

• On a blank sheet of paper…• 1. Draw the set-up of the experiment• 2. Label the Manipulated and Responding

Variables• 3. Results of the experiment• 4. What was Pasteur’s Conclusion?

1-3: STUDYING LIFE

• Are the following things alive?

Characteristics of Living Things

• 1. Living things are made up of cells.– What is a cell?– A collection of living matter enclosed by a barrier that

separates cell from its surroundings.

• 2. Living things reproduce.– Asexual reproduction– Sexual reproduction

• 3. Living things are based on a universal genetic code.– DNA

4. Living things grow and develop.– Development - cells divide to produce new

organisms.– Differentiation - cells change structure to perform

specialized functions.

Characteristics of Living Things

• 5. Living things obtain and use materials and energy.– Grow, Develop, and Reproduce.– Metabolism is combination of chemical reactions

which build up or break down materials.

• 6. Living things respond to their environment.– A stimulus is a signal to which an organism

responds.– External or Internal Stimuli

• 7. Living things maintain a stable internal environment.– Homeostasis – process most organisms use to

keep fairly constant internal temperature and water content.

• 8. Taken as a group, living things change over time.– Organisms evolve or change over time.– Occurs over thousands or millions of years.

Characteristics of Life Mini Activity

• You are observing a potentially new form of life. You record these observations.

• 1. It increases in mass when exposed to water.• 2. It is made up of many tiny circular structures all

connected together.• 3. It changes its shape in response to touch.• 4. There are others like it having the same size,

structure, and coloration.• Is it alive? Explain your answer.

Mini Activity

• This potential life form is not alive.

• Many non-living things will change size, shape, mass, when exposed to outside factors and conditions.

Branches of Biology

• Botany

• Zoology

• Paleontology

Levels of Organization

• Living things studied at different levels.

• See the handout.

• Page 21 of your textbook.

1-4: Tool and Procedures• Compound Light Microscope – focus visible light

rays

• Electron Microscope – focuses beams of electrons

• Metric System of Measurement– Meter (m)– Gram (g)– Liter (l)

The Spaceship Called Earth

• no longer a planet without end

• we must protect our planet and preserve its living treasures

• Earth is like a spaceship with a living cargo, carrying limited amounts of supplies

The Metric System

• the universal system of measurement

• decimal system based multiples of 10

• International System of Units, or SI

Common Metric Units• length

– basic unit is the meter– roughly equals 39.4 inches – a little longer than a yard

• volume: the amount of space an object occupies– basic units are the cubic

centimeter for solids or the liter for liquids

– a liter contains slightly more liquid than a quart

More Common Metric Units• mass: measure of the amount of matter in and

object and weight: measure of the pull of gravity on that mass– on earth, mass and weight can be used

interchangeably– basic unit is the kilogram– approximately 2.2 pounds

• temperature– uses the Celsius scale– water freezes at 0°C and boils at 100°C

Common Metric Prefixes

• kilo: 1,000• hecto: 100• deca: 10• deci: 1/10 • centi: 1/100• milli: 1/1,000• micro: 1/1,000,000• nano: 1/1,000,000,000

1-4: Safety in the Laboratory• only in the laboratory can

you see, touch, and manipulate living systems to understand them more thoroughly

• it is important to follow certain basic safety precautions

• the single most important rule in the laboratory is always follow your teacher’s instructions and the directions exactly

Question of the Day

• 4.5 km is equal to how many meters?

• A. 450 m• B. 4.5 x 103 m• C. 0.0045 m• D. 4500 g

Question: Answered

• The correct answer is B

• Why is D not the correct answer?