What is Biology?

Lesson Objectives:

- Identify the goal of science- Describe how scientists study the

natural world - Explain how and why scientists do

experiments- Describe types of scientific

investigations- Explain what a scientific theory is

Introduction

Think about comparison-shopping and what is Think about comparison-shopping and what is involved in the process.involved in the process.

How is comparison-shopping similar to science?How is comparison-shopping similar to science?

Both involve posing questions, making observations,analyzing data, and drawing conclusions

True or False1. There is a single scientific method that all scientists 1. There is a single scientific method that all scientists follow.follow.

2. Science is based only on data and involves no 2. Science is based only on data and involves no creativity.creativity.

3. Without an experiment, a study is not scientific.3. Without an experiment, a study is not scientific.

4. Scientific ideas are always changing so they can’t be 4. Scientific ideas are always changing so they can’t be trusted.trusted.

5. Scientific data can prove that hypotheses are true or 5. Scientific data can prove that hypotheses are true or false. false.

All of the above statements are common misconceptions of science.

What is Science?

Science is Science is a systematic way of a systematic way of investigating the natural worldinvestigating the natural world

Science begins by Science begins by making observations making observations and asking questionsand asking questions

Questioning Questioning thethe natural world natural world

Explain Explain naturenature and and analyzeanalyze life’slife’s questionsquestions

Purpose of Science

Make important breakthroughs and discoveriesMake important breakthroughs and discoveries

Understand and improve our livesUnderstand and improve our lives

Show our impact on the world around usShow our impact on the world around us

Impacts of Science

MedicineMedicine

TechnologyTechnology

AgricultureAgriculture

ForensicsForensics

GenomicsGenomics

Can Science Change?

Scientific knowledge is Scientific knowledge is NOTNOT absolute truth absolute truth

Reliant on Reliant on REVIEWREVIEW and can be subject to and can be subject to CHANGECHANGE

Example: Periodic Table (addition of new Example: Periodic Table (addition of new elements)elements)

1.1. State the State the ProblemProblem

2.2. Form a Form a HypothesisHypothesis

3.3. ExperimentationExperimentation

4.4. Collecting and Measuring Collecting and Measuring DataData

5.5. Interpreting Data (Constructing Interpreting Data (Constructing GraphsGraphs))

6.6. Draw Draw ConclusionsConclusions

7.7. PublishPublish findings findings

Steps to the Scientific Method

1. State the ProblemBased on OBSERVATIONS

INFERENCES: logical assumptions based on observations by using prior knowledge

- Educated guess- Educated guess

- Possible answer to your - Possible answer to your questionquestion

- - TESTABLETESTABLE

- Written as an - Written as an ““If…thenIf…then……”” statement statement

2. Form a HypothesisWhy is this event

happening?

3. ExperimentationWay to test the hypothesisWay to test the hypothesis

Independent VariableIndependent Variable: scientist changes (: scientist changes (manipulatedmanipulated))

Dependent VariableDependent Variable: scientist observes and measures : scientist observes and measures ((respondingresponding))

ControlControl: used for : used for comparisoncomparison; remains the same; no ; remains the same; no changechange

So, So, independent variable influences change in the independent variable influences change in the dependent variabledependent variable

Repeated trials Repeated trials to ensure accurate datato ensure accurate data

a.a. Qualitative DataQualitative Data: : characteristics, characteristics, physical traits, physical traits, wordswords

b.b. Quantitative Quantitative DataData: numbers, : numbers, quantities, how quantities, how many?many?

4. Collecting and Measuring Data

a.a. Types of Graphs:Types of Graphs:

1. Line Graph – shows a relationship between IV and 1. Line Graph – shows a relationship between IV and DVDV

5. Interpret Data

a. Types of Graphs:a. Types of Graphs:

2. Bar Graph – shows a comparison between 2. Bar Graph – shows a comparison between IV and DVIV and DV

a.a. Types of Graphs:Types of Graphs:

3. Pie Graph – shows percentages; must add 3. Pie Graph – shows percentages; must add up to 100%up to 100%

b.b. Graphs must have:Graphs must have:

TitleTitleKeyKeyLabeled AxesLabeled Axes

X Axis X Axis IV IVY Axis Y Axis DV DV

a.a. Use Use datadata to make summaries to make summaries

b.b. Discussion of Discussion of problemsproblems with with experimentexperiment

c.c. Discussions of Discussions of optionsoptions for for future experimentsfuture experiments

6. Draw Conclusions

7. Publish Findings

Publish in scientific journals so other scientists can evaluate your findings.

RememberRemember……

1.1. Start with a Start with a questionquestion

2.2. Determine a Determine a possible solutionpossible solution

3.3. Test your questionTest your question

4.4. Draw conclusions Draw conclusions based on your based on your findingsfindings

5.5. Let others know Let others know your findingsyour findings

Theory and Law

Scientific TheoryScientific Theory

A hypothesis that has been supported by multiple A hypothesis that has been supported by multiple scientistsscientists’’ experiments in multiple locations experiments in multiple locations

NOT PROVENNOT PROVEN

Example: Theory of Evolution, Big Bang TheoryExample: Theory of Evolution, Big Bang Theory

A Scientific LawA Scientific Law

a description of what we find happening in nature a description of what we find happening in nature over and over again in a certain wayover and over again in a certain way

Example: Law of gravity, Newton’s laws of motionsExample: Law of gravity, Newton’s laws of motions

Scientific Method

In Introduction to Biology In Introduction to Biology LearnEd booklet read the LearnEd booklet read the passages and answer the passages and answer the

questions on pages 12-13 in questions on pages 12-13 in your booklet. your booklet.

What is Biology?

BiologyBiology is the study is the study of living and once of living and once living organismsliving organisms

““Bio”-lifeBio”-life

““-ology”-study of-ology”-study of

What do Biologists study?

The interactions of The interactions of lifelife

The interactions with The interactions with the the environmentenvironment

They study They study problemsproblems and propose and propose solutionssolutions (examples: medical (examples: medical treatment, disease treatment, disease prevention, etc.)prevention, etc.)

What makes a living thing alive?What makes a living thing alive?

What do you think are the most important What do you think are the most important characteristics of ALL living organisms?characteristics of ALL living organisms?

What are the living things in the picture below?

There are 8 characteristics of Life: There are 8 characteristics of Life: Cellular OrganizationCellular Organization

ReproductionReproduction

Metabolism (Obtain and Use Energy)Metabolism (Obtain and Use Energy)

HomeostasisHomeostasis

HeredityHeredity

ResponsivenessResponsiveness

Growth and DevelopmentGrowth and Development

Adapt Through EvolutionAdapt Through Evolution

Unicellular-composed of one cellUnicellular-composed of one cell

Ex: Bacteria, amoeba, paramecium, Ex: Bacteria, amoeba, paramecium, euglenaeuglena

Multicellular- composed of many cells Multicellular- composed of many cells

Ex: Humans Ex: Humans

Cellular Organization:Cellular Organization:

Cell------Smallest unit capable of all life functionsCell------Smallest unit capable of all life functions

Reproduction is the process of producing new Reproduction is the process of producing new organisms of the same typeorganisms of the same type

Asexual ReproductionAsexual ReproductionA single parent organism reproducing by itselfA single parent organism reproducing by itself

Sexual ReproductionSexual ReproductionTwo different parent organisms contribute genetic Two different parent organisms contribute genetic information information

Involves the combination of male and female sex Involves the combination of male and female sex cellscells

Living organisms need Living organisms need energy to energy to grow, develop, repair damage, and grow, develop, repair damage, and reproducereproduce

MetabolismMetabolism

The total of The total of all all chemical reactions in chemical reactions in an organisman organism

Keeping the internal environment of the Keeping the internal environment of the cell or organism within the ranges cell or organism within the ranges required for liferequired for life

Body temperatureBody temperature

Blood volumeBlood volume

pH balancepH balance

Water balanceWater balance

Genes carry hereditary information

Genes are composed of DNA

Heredity is the reason children resemble their parents

Mutations change DNA code and can be passed from generation to generation

Organisms react to stimuliOrganisms react to stimuli::

LightLight

TemperatureTemperature

OdorOdor

Sound Sound

GravityGravity

HeatHeat

WaterWater

PressurePressure

An example is a plant’s An example is a plant’s leaves and stems growing leaves and stems growing toward lighttoward light

Growth means to Growth means to get bigger in sizeget bigger in size

Development involves Development involves a change in the a change in the physical form or physiological make-up of physical form or physiological make-up of an organisman organism

AdaptationAdaptation

A process that A process that enables enables organisms to become better organisms to become better suited to their environmentsuited to their environment

Species obtain adaptations Species obtain adaptations through evolution over great through evolution over great periods of timeperiods of time

An Example of AdaptationAn Example of Adaptation

Desert plants have succulent waxy leaves and Desert plants have succulent waxy leaves and stems to store water and reduce water lossstems to store water and reduce water loss

Characteristics of Life

Cellular OrganizationCellular Organization

ReproductionReproduction

Metabolism (Obtain Metabolism (Obtain and Use Energy)and Use Energy)

HomeostasisHomeostasis

HeredityHeredity

ResponsivenessResponsiveness

Growth and Growth and DevelopmentDevelopment

Adapt Through Adapt Through EvolutionEvolution