Chapter 1 Science of BiologyChapter 1 Science of Biology

1-1 What is Science?1-1 What is Science?

A. What science is A. What science is

1. Goals of science1. Goals of science

a. a. Investigate, understand, and explainInvestigate, understand, and explain eventsevents of the of the natural worldnatural world

b. Use experiments to make b. Use experiments to make predictionspredictions

2. science definition2. science definition

a. Organized way of using evidence to a. Organized way of using evidence to learn learn about the natural world about the natural world

--knowledge gained through --knowledge gained through experimentsexperiments

3. Science is different from other areas of 3. Science is different from other areas of studiesstudies a. Science looks at natural worlda. Science looks at natural world

b. Information is collected and organized in b. Information is collected and organized in an an orderly manner orderly manner

c. Explanations are proposed which can be c. Explanations are proposed which can be tested tested

B. Thinking like a scientistB. Thinking like a scientist

1. observation1. observation a. Gathering information by using a. Gathering information by using

sensessenses 2. data2. data

a. Gathered informationa. Gathered information b. 2 typesb. 2 types --quantitative: expressed as --quantitative: expressed as

numbersnumbers(counting, measuring)(counting, measuring)

--qualitative: qualities which cannot --qualitative: qualities which cannot be be counted, usually rely on senses, counted, usually rely on senses, opinionopinion

(He is tall.)(He is tall.) 3. inference3. inference

a. Logical interpretation based on a. Logical interpretation based on knowledge or experience knowledge or experience

b. Water test exampleb. Water test example

C. Explaining and Interpretating EvidenceC. Explaining and Interpretating Evidence

1. Events are explained logically and 1. Events are explained logically and analyticallyanalytically

2. Hypothesis2. Hypothesis

a. Proposed after observationa. Proposed after observation

b. Explanation of observationsb. Explanation of observations

c. Based on prior knowledgec. Based on prior knowledge

d. A logical inferenced. A logical inference

e. Uses creative, informed imaginatione. Uses creative, informed imagination

f. Must be testable f. Must be testable

--through experiments --through experiments

-- by gathering more data (food -- by gathering more data (food poison)poison)

g. Can be confirmed, disproved or g. Can be confirmed, disproved or changedchanged

D. Science as a way of knowingD. Science as a way of knowing

1. Ongoing process1. Ongoing process of change and of change and advancing advancing understanding understanding

a. By asking questions, observing, a. By asking questions, observing, making making inferences , testing inferences , testing hypothesishypothesis

b. New tools, techniques, discoveriesb. New tools, techniques, discoveries

2. Characteristics of a Scientist2. Characteristics of a Scientist

a. Skeptical, open-minded, curious, a. Skeptical, open-minded, curious, knows knows science has limits science has limits

E. Science and Human ValuesE. Science and Human Values

1. Understanding science aids humans in 1. Understanding science aids humans in making making informed decisions and living informed decisions and living within the laws within the laws of society of society

2. Scientists make recommendations and 2. Scientists make recommendations and citizens citizens use those recommendations to use those recommendations to make societal make societal decisions decisions

1-2 How Scientists work1-2 How Scientists work

A. Designing an experimentA. Designing an experiment 1. Observe, question, identify the 1. Observe, question, identify the

problemproblem 2. Form a hypothesis2. Form a hypothesis

3. Set up a controlled experiment3. Set up a controlled experiment a. Variable: factors which changea. Variable: factors which change

equipment, temperature, light, timeequipment, temperature, light, time --types of variables:--types of variables: *manipulated or independent—*manipulated or independent—

scientist deliberately changesscientist deliberately changes *responding or dependent—*responding or dependent— changes in response to changes in response to manipulated variablemanipulated variable *control or constant or *control or constant or

comparison—comparison— does not change throughout the does not change throughout the

experimentexperiment

4. Observe and gather data4. Observe and gather data

a. Must be organized and a. Must be organized and accurately accurately recorded recorded

5. Analyze data5. Analyze data

6. Form a conclusion from data 6. Form a conclusion from data analysisanalysis

a. Is Hypothesis confirmed, a. Is Hypothesis confirmed, proven proven wrong or needing wrong or needing clarification?clarification?

7. Repeat experiment numerous 7. Repeat experiment numerous timestimes

8. Publish results 8. Publish results

B. Experiments on Spontaneous B. Experiments on Spontaneous GenerationGeneration

1. Spontaneous generation1. Spontaneous generation

a. living organisms arise from a. living organisms arise from non-non- living matter (raw meat living matter (raw meat produces produces maggots) maggots)

2. Handouts2. Handouts

a. Redia. Redi

b. Needhamb. Needham

c. Spallanzanic. Spallanzani

d. Pasteurd. Pasteur

C. When experiments are not possibleC. When experiments are not possible

1. field experiments1. field experiments

a. Observe large groups of a. Observe large groups of organisms organisms in their habitat in their habitat

b. Must follow scientific method b. Must follow scientific method to be to be valid valid

D. Theory DevelopmentD. Theory Development

1. Theory1. Theory

a. Well supported idea or a. Well supported idea or explanation, explanation, not testable not testable

b. Broad range of observations b. Broad range of observations tied tied together together

c. Can be revised or replaced as c. Can be revised or replaced as new new info becomes available info becomes available

1-3 Studying Life1-3 Studying Life

A. Biology/biologistA. Biology/biologist

1. study of 1. study of

a. Bio-lifea. Bio-life

b. -ology means study ofb. -ology means study of

2. science (scientist) to understand the living 2. science (scientist) to understand the living world by using the scientific method world by using the scientific method

B. Characteristics of Living Things (8)B. Characteristics of Living Things (8)

1. Composed of cells1. Composed of cells

a. Cella. Cell

--collection of living matter--collection of living matter

--separated from surroundings by a --separated from surroundings by a barrierbarrier

--smallest unit to be considered --smallest unit to be considered alivealive

--complex, high organized --complex, high organized

b. Cell organism type (by number)b. Cell organism type (by number)

--Single celled or unicellular--Single celled or unicellular--multicellular-organism made up of--multicellular-organism made up of many cells, cells are highly many cells, cells are highly

diverse, diverse, highly specialized highly specialized2. reproduction2. reproduction a. 2 typesa. 2 types

--asexual requires 1 parent, cell --asexual requires 1 parent, cell divides, splits, or buds divides, splits, or buds

--sexual requires 2 parents (male---sexual requires 2 parents (male- sperm/female-egg), 2 sperm/female-egg), 2

cells form first cells form first single cell of new single cell of new organism called a organism called a zygote zygote

3. based on a genetic code (DNA/RNA)3. based on a genetic code (DNA/RNA)

4. Growth and development4. Growth and development

a. Growa. Grow

--increase in size--increase in size

--unicellular cells only grow--unicellular cells only grow

b. Developmentb. Development

--cells become different with --cells become different with different different functions or even look functions or even look differentdifferent

ex. Cartilage forms boneex. Cartilage forms bone

pubertypuberty

c. Organisms have distinctive life c. Organisms have distinctive life cyclescycles

--egg, larva, pupa, adult--egg, larva, pupa, adult

--humans --humans

5. Need for materials and energy 5. Need for materials and energy

a. Metabolisma. Metabolism

--chemical reactions to build up --chemical reactions to build up or or break down materials break down materials needed for life needed for life processes processes

--anabolism is to build up --anabolism is to build up meat>protein>musclemeat>protein>muscle

--catabolism is to break down--catabolism is to break down

bread>carbohydrates>energybread>carbohydrates>energy

6. Response to environment6. Response to environment

a. Respond to stimuli (signal)a. Respond to stimuli (signal)

b. For survivalb. For survival

7. Maintaining an internal balance 7. Maintaining an internal balance

a. Homeostasis--Internal conditions a. Homeostasis--Internal conditions must be must be in balancein balance

b. Controlled by internal feedback b. Controlled by internal feedback systemsystem

--blood pressure, heart rate, --blood pressure, heart rate, temperature temperature regulation, glucose regulation, glucose levellevel

8. Evolution8. Evolution

a. Change over timea. Change over time

C. Branches (Fields) of Biology C. Branches (Fields) of Biology

1. based on size, type, or perspective1. based on size, type, or perspective

2. Handout2. Handout

D. Biology in Everyday lifeD. Biology in Everyday life

1. Every factor of your life is affected by 1. Every factor of your life is affected by biologybiology

a. Foods you eat (quantity, temp., storage a. Foods you eat (quantity, temp., storage of)of)

b. Health—cleanliness, attitude about b. Health—cleanliness, attitude about drugs, drugs, sexsex

c. Diseasec. Disease

d. Fueld. Fuel

e. Environmental factorse. Environmental factors

2. Voting societal members will make 2. Voting societal members will make decisionsdecisions

based on knowledge of biologybased on knowledge of biology

1-4 Tools and Procedures1-4 Tools and Procedures

A. Metric System (SI system)A. Metric System (SI system)

1. decimal system1. decimal system

2. multiples of 10s2. multiples of 10s

3. prefixes3. prefixes

kilo (K, 1000); hecto (h, 100); deka (da, 10);kilo (K, 1000); hecto (h, 100); deka (da, 10);

deci (d, 0.1); centi (c, 0.01); milli (m, 0.001)deci (d, 0.1); centi (c, 0.01); milli (m, 0.001)

4. bases or units4. bases or units

length (meter, m); mass (gram, g); length (meter, m); mass (gram, g);

liquid volume (Liter, L); solid volume (cmliquid volume (Liter, L); solid volume (cm3, 3,

mm33); temperature (Celsius, C); temperature (Celsius, C00—SI unit, —SI unit, Kelvin, K--scientific) Kelvin, K--scientific)

5. easy conversion—move decimal to right or 5. easy conversion—move decimal to right or left left

B. Analyzing Biological DataB. Analyzing Biological Data

1. graphs/tables make patterns 1. graphs/tables make patterns easier to see easier to see

2. tools—computers, balances, 2. tools—computers, balances, microscopes microscopes

C. MicroscopesC. Microscopes

1. produces magnified images too 1. produces magnified images too small tosmall to

be seen by an unaided eyebe seen by an unaided eye

2. Types2. Types

a. Compound light microscopea. Compound light microscope

--magnifies up to 1000x--magnifies up to 1000x

--light passes through 2 lenses --light passes through 2 lenses (eyepiece, objective) (eyepiece, objective)

--used to observe live organisms--used to observe live organisms

--stains are used for clarification--stains are used for clarification

--stains kill a live organism --stains kill a live organism b. Electron microscopeb. Electron microscope --uses beams of electrons to --uses beams of electrons to

produce produce images images --magnifies 1000x more than light --magnifies 1000x more than light

microscope microscope --2 types--2 types

transmission electron (TEM)transmission electron (TEM)shines electrons through shines electrons through

thin thin specimen giving details specimen giving details inside inside the cellthe cell

scanning electron (SEM)scanning electron (SEM)shines electrons back and shines electrons back and

forth forth across the surface across the surface giving a 3D giving a 3D image of surfaceimage of surface

TEM/SEM only used in a vacuum, TEM/SEM only used in a vacuum, organism is preserved organism is preserved

and and dehydrateddehydrated

D. Lab TechniquesD. Lab Techniques

1. Cell culture1. Cell culture a. Single cell is placed in a nutrient a. Single cell is placed in a nutrient

solution (agar) and grows into solution (agar) and grows into a group a group of cells of cells

b. Used to test cell responses or cell b. Used to test cell responses or cell interactions w/other interactions w/other

substancessubstances c. Cultures are viewed under a c. Cultures are viewed under a

microscopemicroscope 2. cell fractionation2. cell fractionation

a. Separates cell parts from each othera. Separates cell parts from each other b. Machine called a centrifuge which b. Machine called a centrifuge which

spins spins several hundred times/min. several hundred times/min. ex.: separates blood (plasma, ex.: separates blood (plasma,

platelets, platelets, cholesterol for testing) with cholesterol for testing) with most most dense settling to bottomdense settling to bottom

E. Lab SafetyE. Lab Safety