Introductory The World of Life Science Chapter 1 Table of

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The World of Life Science

Section 1 Asking About Life Section 2 Scientific Methods Section 3 Scientific Models Section 4 Tools, Measurement, and Safety

Introductory

Chapter 1

Table of Contents



Section 1 Asking About Life Introductory

Chapter

• Explain the importance of asking questions in science. • State examples of life science at work. • List three ways life science is beneficial to living things.

Objectives




Chapter

It All Starts with a Question

• Life Science is the study of living things. • In your Own Backyard You can ask questions about familiar organisms. • Touring the World The questions you ask about your neighborhood are just a sample of all the questions you could ask about the world.




Chapter

Life Scientists

• Who are life scientists? • Anyone Women and Men from any cultural background can become life scientists. • Anywhere Life scientists carry out investigations in laboratories, on farms, in forests, on the ocean floor––even in space! • Anything Life scientists study any thing that is a live, or that used to be alive, that interests them.




Chapter

Why Ask Questions?

• Fighting Diseases Science has led to many life-saving discoveries, such as the vaccination for polio. • Understanding Inherited Diseases By learning about how some diseases are inherited and how they affect people, scientists hope to find ways to prevent or cure these diseases.




Chapter

Why Ask Questions? continued

• Protecting the Environment Understanding how we affect the world around us is the first step in finding solutions to problems such as pollution and the extinction of wildlife.



Section 2 Scientific Methods Introductory

Chapter

• Describe scientific methods. • Determine the appropriate design of a controlled experiment. • Use information in tables and graphs to analyze experimental results. • Explain how scientific knowledge can change.

Objectives




Chapter

What Are Scientific Methods?

• Scientific methods are the ways in which scientists answer questions and solve problems.




Chapter

Scientific Methods

Click below to watch the Visual Concept.

You may stop the video at any time by pressing

the Esc key.

D:/student/ch01/sec02/vc00/hl501_02_v00fs.htm




Chapter

1. Make Observations

• Accurate Observations Any information that you gather through your senses is an observation. Scientist use standard tools and methods to make and record observations.




Chapter

2. Ask a Question

• Asking a question helps focus the purpose of the investigation. Scientists often ask a question after making an observation.

• For example, students observing deformed frogs might ask, “Could something in the water be causing the deformities?”




Chapter

3. Form a Hypothesis

• A hypothesis is a possible explanation or answer to a question that is based on observation and can be tested. • A statement of cause and effect that can be used to set up a test for a hypothesis is called a prediction.





Chapter

A Hypothesis Makes Predictions




Chapter

4. Test the Hypothesis (Experiment)

• Under Control A controlled experiment tests only one factor at a time and consists of a control group and one or more experimental groups.





Chapter

A controlled experiment must have a

control group and an experimental group!!

• Designing an Experiment Designing a good experiment requires planning and a consideration of all factors.




Chapter

5. Collect Data and Analyze the Results

• After they finish their tests, scientists must analyze the results. Analyzing the results helps scientists explain and focus on the effect of the variable.




Chapter

6. Draw Conclusions

• Scientists must conclude if the results of their tests support the hypothesis. Proving that a hypothesis is not true can be as valuable as proving that it is true.




Chapter

7. Communicate Results

• After finishing an investigation, scientists communicate their results. • Sharing allows other scientists to repeat experiments to see if they get the same results. • Sometimes, new data lead scientists to change their hypotheses.




Chapter



Section 3 Scientific Models Introductory

Chapter

• Give examples of three types of models. • Identify the benefits and limitations of models. • Compare the ways that scientists use hypotheses, theories, and laws.

Objectives




Chapter

Types of Scientific Models

1. Physical Models Physical models, such as miniature volcanoes and steam engines, look like the thing that they model.

2. Mathematical Models A mathematical model may be made up of numbers, equations, and other forms of data. Charts and graphs are examples of mathematical models.




Chapter

Types of Scientific Models, continued

3. Conceptual Models Conceptual models are systems of ideas or comparisons of unfamiliar things with familiar things to help explain unfamiliar ideas.

Ex. How life began from chemicals




Chapter

Mathematical Model: A Punnett Square

• The Punnett square helps scientists study the passing of traits from parents to offspring.




Chapter

Building Scientific Knowledge

• Scientific Theories An explanation that ties together many related observations, facts, and tested hypotheses is called a theory.

• Scientific Laws A scientific law is a statement of what will happen in a specific situation. A law tells you how things work.

• Scientific Change If new evidence challenges an accepted idea, scientists must reexamine the old evidence and reevaluate the old idea.




Section 4 Tools, Measurement, and Safety Introductory

Chapter

• Give three examples of how life scientists use computers and technology. • Describe three tools life scientists use or observe organisms. • Explain the importance of the International System of Units, and give four examples of SI units.

Objectives



Section 4 Tools, Measurement, and Safety

Introductory

Chapter

Computers and Technology

• Technology is the application of sciences for practical purposes.

• Computers are used to create graphs, solve complex equations, and analyze and communicate data.



Section 4 Tools, Measurement, and Safety

Introductory

Chapter

Tools for Seeing

• Compound Light Microscope is an instrument that uses two or more lenses to magnify small organisms.

• Electron Microscopes focuses a beam of electrons to magnify objects.

• Although electron microscopes produce clearer and more detailed images than light microscope, they cannot be used to observe living things.






Chapter

Units of Measurement

• The International System of Units Begun by the French Academy of Sciences in the late 1700s, the SI is used by almost all countries in the world.

• All SI units are based on the number 10, which makes conversion from one unit to another easy.




Chapter




Chapter

Measurement

• Length The basic unit of length in the SI is the meter. • Area The measure of how much surface an object has. Use the following equation:

area length width

• Volume The measure of the size of a body or region in three-dimensional space. Volume video





Chapter

Measurement, continued

•Mass A measure of the amount of matter in an object. • Temperature The measure of how hot (or cold) something is.




Chapter

Measuring Temperature




Chapter

Safety Rules!

• Follow your teacher’s instructions. • Read lab procedures carefully. • Pay special attention to safety information.



Concept Map

Use the terms below to complete the concept map on

the next slide.

scientific methods

observations

controlled experiments

drawing conclusions

scientists

questions

The World of Life Science Introductory

Chapter



The World of Life Science Introductory

Chapter

scientific methods

observations

controlled experiments

drawing conclusions

scientists

questions

flipchart

//Prfile-02/StaffData$/jchriste/My Documents/A. Science 7 III/Chapter 1 Scientific Method/concept map.flipchart



Interpreting Graphics

The table below shows the plans for an experiment in

which bees will be observed visiting flowers. Use the

table to answer the questions that follow.

Introductory

Chapter Standardized Test Preparation



1. Which factor is the

variable in this

experiment?

A the type of bee

B the time of day

C the type of plant

D the color of the

flowers

Introductory




1. Which factor is the

variable in this

experiment?

A the type of bee

B the time of day

C the type of plant

D the color of the

flowers

Introductory




Introductory




2. Which of the following hypotheses could be tested by

this experiment?

F Honeybees prefer to visit rose plants.

G Honeybees prefer to visit red flowers.

H Honeybees prefer to visit flowers in the morning.

I Honey bees prefer to visit Portland rose flowers

between 9 and 10 A.M.

Introductory




2. Which of the following hypotheses could be tested by

this experiment?

F Honeybees prefer to visit rose plants.

G Honeybees prefer to visit red flowers.

H Honeybees prefer to visit flowers in the morning.

I Honey bees prefer to visit Portland rose flowers

between 9 and 10 A.M.

Introductory




Introductory




3. Which of the following is the best reason why the

Portland rose plant is included in all of the groups to

be studied?

A The type of plant is a control factor; any type of

flowering plant could be used as long as all plants

were of the same type.

B The experiment will test whether bees prefer the

Portland rose over other flowers.

C An experiment should always have more than one

variable.

D The Portland rose is a very common plant.

Introductory




3. Which of the following is the best reason why the

Portland rose plant is included in all of the groups to

be studied?

A The type of plant is a control factor; any type of

flowering plant could be used as long as all plants

were of the same type.

B The experiment will test whether bees prefer the

Portland rose over other flowers.

C An experiment should always have more than one

variable.

D The Portland rose is a very common plant.

Introductory
