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Welcome to Biology 101

1. Name

2. Major/Program of study

3. Favorite living organism

4. Preferred email

5. What do you hope to learn from the course? What are your learning goals?

6. List any other college level science courses you have taken.

Write on the

scrap paper

Learning Goals

Compare and contrast science to other

disciplines

Describe properties of living things

Understand the scientific process and

be able to design a sound experiment

Recognize the four unifying theories of

biology

Become familiar with how biologists

classify/organize the diversity of life

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Group discussion:

“ How does science

differ from other ways

of knowing or

thinking about

things?”

Following the steps…

Interpretation of Results and Conclusions

Observation of a Scientific Phenomenon

Scientific Research Question

Hypothesis

Prediction

Methods/Experimental Design

Data Collection and Analysis/Results

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Research Questions • Testable (measurable)

• Well defined

• Interesting– builds upon our scientific knowledge

1. Does eating extra kale increase your bone density and strength as much as drinking milk?

2. Are tall people good at basketball? 3. Do animals and trees have an eternal

soul? 4. Are there angels?

Following the steps…

Interpretation of Results and Conclusions

Observation of a Scientific Phenomenon

Scientific Research Question

Hypothesis

Prediction

Methods/Experimental Design

Data Collection and Analysis/Results

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Hypothesis

• Hypothesis: Explains WHY or HOW we think something works

• Falsifiable

• Testable

• Can a hypothesis proven true?

• NO! We find support for our hypothesis, or find little evidence for it, etc.

Predictions Why do we need predictions if we have a hypothesis?

Proper form of a prediction If……then….

If (the hypothesis is true), then (expectation)

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Predictions

Example:

Hypothesis: Tall people are

good at basketball

Prediction: IF tall people are

good at basketball, THEN they

will score more points than

shorter players.

Which is the hypothesis?

Which is a prediction?

A. Light is necessary for lettuce seed

germination.

B. Lettuce seeds placed in a dark room

will not germinate.

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Following the steps…

Interpretation of Results and Conclusions

Observation of a Scientific Phenomenon

Scientific Research Question

Hypothesis

Prediction

Methods/Experimental Design

Data Collection and Analysis/Results

Experimental design

Independent (explanatory) variables

– What are you TESTING? What variable are you manipulating?

– What are your TREATMENTS and “CONTROL”

– Not affected by other variables

Dependant Variable/Response variable

– What are you MEASURING?

– A factor that DEPENDS on the independent variable

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Experimental design

Control variables: what other things

might influence your response variable

(what you are measuring)?

How can you minimize their effect in the

experiment?

Question

The hypothesis in a seed germination experiment is:

Light is necessary for lettuce seed germination .

Groups of lettuce seeds are placed in light with

warm temperatures and adequate moisture.

Another set of identical seeds is placed in the dark

under the same conditions.

What is the dependent variable?

a. Light

b. Temperature

c. Germination rate

d. Type of plant

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Elements of a good

Experimental design:

Replication: more than one experimental

unit

Randomization: you must randomly

assign treatments/control

Independence: the replicates MUST be

separate from each other

Example: Is kale good

for strong bones?

HYPOTHESIS:

High levels of calcium in Kale will lead to increases in bone density

PREDICTIONS:

IF High levels of calcium in Kale will lead to increases in bone density, THEN people eating more kale will have higher bone

density than people lacking Kale from their diet.

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Following the steps…

Interpretation of Results and Conclusions

Observation of a Scientific Phenomenon

Scientific Research Question

Hypothesis

Prediction

Methods/Experimental Design

Data Collection and Analysis/Results

Interpretation of Data

INDEPENDENT!

DEP

END

ENT!

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Discussion question

What is the difference between scientific

hypotheses and theories?

What might the graph look

like? Scenario: The hypothesis in a seed germination

experiment is: Light is necessary for lettuce

seed germination . Groups of lettuce seeds are

placed in light with warm temperatures and

adequate moisture. Another set of identical

seeds is placed in the dark under the same

conditions.

1. Come up with a well-defined prediction.

2. Sketch a graph of your prediction for this

experiment, labeling the axes

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Group discussion

What qualifies something as “living” versus “nonliving?”

A life-defining property must be exclusive to living things…

~5 min

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Basic Properties of Life 1. Cells

2. Metabolism

all living things process energy which is used to power other processes

3. Homeostasis

all living things maintain stable internal environments to optimize conditions for metabolism and other processes

4. Growth and reproduction

5. Heredity

all organisms pass genetic information across

generations from parents to offspring

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Four Theories Unify Biology as

a Science

Cell Theory

Theory of Evolution

Gene Theory

Theory of Heredity

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The Cell Theory: Organization of Life

Robert Hooke, 1665

Discovered cells

Anton van Leeuwenhoek, 1670s

Discovered single-celled life

Matthias Schleiden & Theodor Schwann, 1839

All living organisms are composed of cells

Cells are the basic units of life

Later the third tenet of the theory was added

All cells come from other cells

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Genetic information is encoded in molecules of

deoxyribonucleic acid (DNA)

Genes can encode specific proteins or RNA, or

they can act to regulate other genes

The proteins and RNA encoded by an

organism’s genes determine what it will be like

in terms of form and function

The Gene Theory: Molecular Basis

of Inheritance

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Figure 1.12 The

gene theory

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

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2

3

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MACROPHAGE

NERVE CELL

INTESTIONAL CELL

Nucleus

Chromosomes

Genes

being

used

MUSCLE CELL

Chromosome Gene

DNA double helix

Nucleotides

All cells contain the same

set of genes, but different kinds

of cells use different genes.The

production of specific proteins

coded for by these genes

determines what the cell is like.

A typical human

chromosome can contain

up to a thousand genes,

arrayed along a linear

piece of DNA.

Each gene is composed of a sequence of several hundred

to many thousands of DNA nucleotides and functions as a

discrete unit of information.

A human cell has 46

chromosomes, containing

some 3 billion nucleotides

of DNA.

1 A human body

contains over 100

different kinds of cells.

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Genes are passed down in generations

as discrete units

Mendel’s theory of heredity gave rise

to the field of genetics

The Theory of Heredity: Unity of Life

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Charles Darwin’s theory of evolution explains the unity and diversity of life as “descent with modification”

Tomorrows topic!

The Theory of Evolution: Diversity

of Life

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Scientific Theory

a. Presence or absence of

oxygen.

b. The bacterium that causes

botulism (Clostridium

botulinum) only grows in

sealed cans.

c. Clostridium botulinum

cannot grow in an

environment where

oxygen is present.

d. Support or reject the

hypothesis.

e. A growth medium with all

the nutrients required by

Clostridium botulinum.

f. Amount of bacteria growth

recorded

Botulism is a rare but serious illness usually caused by improperly canned food. Botulism eventually causes

paralysis of the muscles. Based on the information provided in the concept map, place the letter with the

appropriate question.

What is the

observation?

An experiment is

conducted.

What is the

hypothesis?

What is the

conclusion?

What is the control

variable?

What is the

dependent

variable? What is the

independent

variable?

Scientific Theory Key

a. Presence or absence of

oxygen.

b. Why does the bacterium

that causes botulism

(Clostridium botulinum)

only grow in sealed cans?

c. Clostridium botulinum

cannot grow in an

environment where

oxygen is present.

d. Support or reject the

hypothesis.

e. A growth medium with all

the nutrients required by

Clostridium botulinum.

f. Amount of bacteria growth

recorded

What is the

observation?

An experiment is

conducted.

What is the

hypothesis?

What is the

conclusion?

What is the control

variable?

What is the

dependent

variable? What is the

independent

variable?

Botulism is a rare but serious illness usually caused by improperly canned food. Botulism eventually causes

paralysis of the muscles. Based on the information provided in the concept map, place the letter with the

appropriate question.

b

e

c

f

d

a