biology i chapter 1 notes the study of life. section 1: intro to biology the science of life bio =...

Biology IChapter 1 NotesThe Study of Life

Section 1: Intro to BiologySection 1: Intro to BiologyThe Science of LifeThe Science of Life

BIO = lifeBIO = life LOGOS = studyLOGOS = study Biology is the study of all living things Biology is the study of all living things

(organisms, or the science of life)(organisms, or the science of life)

-When people study living things or pose -When people study living things or pose questions about how living things interact questions about how living things interact with the environment, they are learning with the environment, they are learning about biology. about biology.

What do biologists “do”?

Study the diversity of life– Jane Goodall learning about chimps, now we can protect them…

Research diseases– From Goodall’s work, Mary King studied chimp DNA to better

understand breast cancer

Develop technologies – Bionic “parts” or artificial limbs, medicine, treatments

Improve agriculture– Genetic engineering to allow plants to grow in nutrient poor soil

or withstand disease; increase production

Preserve the environment– Prevent extinction of animals and plants (captivity programs)

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Characteristics of LifeCharacteristics of Life

1. Made of CELLS: unicellular / multi-cellular

2. Are ORGANIZED

3. GROW and DEVELOP

4. REPRODUCE: ”Like produces like”-Sexual vs. Asexual Reproduction

5. RESPOND to stimuli: either internal or external

6. Require ENERGY

7. Maintain HOMEOSTASIS

8. ADAPTATIONS/EVOLVE over time-occurs in populations, NOT individual organisms

Characteristics of Life

Section 2: The Nature of ScienceWhat is science?

Science: the body of knowledge based on the study of nature (biology, chemistry, physics, Earth science)

In science class we will: Rely on evidence Expand scientific knowledge Challenge accepted theories Question results Test Claims Use peer review Use the metric system: units with divisions that are powers

of ten (International System of Units = SI) (meter = length, gram = mass, liter = volume, second = time)

Characteristics of a “Good” Scientist (OSCO)

1. Observant

2. Skeptical

3. Curious

4. Open-Minded

How curious are you???How curious are you???You throw away the outside and cook the inside. You throw away the outside and cook the inside. Then you eat the outside and throw away the Then you eat the outside and throw away the inside. What did you eat?inside. What did you eat?– ANSWER: an ear of cornANSWER: an ear of corn

What goes around the world but stays in a corner?What goes around the world but stays in a corner?– ANSWER: a stampANSWER: a stamp

Give me food, and I will live; give me water, and I Give me food, and I will live; give me water, and I will die. What am I?will die. What am I?– ANSWER: a fireANSWER: a fire

I'm where yesterday follows today, and tomorrow's I'm where yesterday follows today, and tomorrow's in the middle. What am I?in the middle. What am I?– ANSWER: a dictionaryANSWER: a dictionary

I have hands that wave at you, though I never say I have hands that wave at you, though I never say goodbye. It's cool for you to be with me, especially goodbye. It's cool for you to be with me, especially when I say, "HI.“ What am I?when I say, "HI.“ What am I?– ANSWER: a fanANSWER: a fan

Observations lead to questions… how are they answered?

Science follows a process (AKA scientific method):

1. Ask a Question/Define the Problem– Observations: collected with your senses – Inferences: made with your mind, explain

observations–

Observations/Inferences Video

2. Collect Data/Background information

3. Form a VALID hypothesis– Must make a prediction; must be testable– Must be stated in the “If … then…” format

Section 3: Methods of Section 3: Methods of ScienceScience

4. Collect the Data using a Controlled Experiment

The “independent” variable; the factor that changes; only 1 at a time

The “dependent” variable(s) must be collected as data Quantitative Data: There are 3 mL of fluid; numeric Qualitative Data: The fluid is orange; word description

5. Analyze Data– Graphs (bar or line), Tables, and Charts (pie)

6. Report or Form Conclusions

Section 3: Methods of Science – Cont.Section 3: Methods of Science – Cont.

NAMENAME TIMETIME

FrankFrank 33 sec33 sec

JessicaJessica 27 sec27 sec

Tools of a Biologist: The Microscope Compound Light Microscope

– uses light reflected by two or more lenses– 1 eyepiece, 1 light (light goes through)

Stereoscope (AKA Dissecting Microscope)– 2 eyepieces, 3 light combos (3-D objects)

Electron Microscope– Uses electrons reflected by magnets– Can only be used with non-living specimens

2 Types of Electron Microscopes

A. Scanning Electron Microscope (SEM) electrons bounce off specimen produces 3-D image lower magnification than TEM

B. Transmission Electron Microscope (TEM) electrons travel through the

specimen higher magnification than SEM no 3-D image specimen must be frozen, embedded

in plastic, and sliced into a thin pieceStructure and Function of the Electron Microscope

Microscope Vocabulary Total Magnification

Calculated by multiplying ocular magnification by objective magnification

Field of view What you see when looking

in the eyepiece Gets smaller when you

increase magnification Working Distance

Distance between objectives and stage

Gets smaller when you use the high power objectives

Depth-of-field Occurs when you are looking

closely at the layers of a specimen, you can actually see different layers at the same time!

Stereoscope vs. Compound Light Microscope

•Eyepieces (2 vs. 1):

•2 eyepieces allow for a 3-D image

•Lights (2 vs. 1):

•2 lights allow you to see solid objects

• Size of Object:

•Larger working distances allows you to see bigger things

Think about this . . .Think about this . . . Do mice come from straw?Do mice come from straw? Do frogs come from mud?Do frogs come from mud? Do maggots come from meat?Do maggots come from meat? If you answered no to any of the above questions in If you answered no to any of the above questions in

the 1600's, people would think you were crazy. These the 1600's, people would think you were crazy. These things were all considered to be true facts until the things were all considered to be true facts until the year 1668. year 1668.

Spontaneous GenerationSpontaneous Generation: AKA “abiogenesis”: AKA “abiogenesis”– Living organisms are generated by decaying organic Living organisms are generated by decaying organic

substancessubstances– EX: mice spontaneously appear in stored grain or EX: mice spontaneously appear in stored grain or

maggots spontaneously appear in meat maggots spontaneously appear in meat

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Redi’s Controlled Experiment

OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat.

HYPOTHESIS: If flies land on meat, then maggots will be produced.PROCEDURE

Controlled variables:jars, type of meat,location, temperature,time

Manipulated Variable:gauze covering thatkeeps flies away from meat

Uncovered jars Covered jars

Several days pass

Maggots appear No maggots appear

Responding Variable: whether maggots appearCONCLUSION: Maggots form only when flies come in contact with meat.

Spontaneous generation of maggots did not occur.

Section 1-2

Go to Section:

HYPOTHESIS– Possible explanation– Educated guess

THEORY– Explanation that has been tested and not

yet disproved– EX: Theory of Evolution, Theory of Relativity

LAW– Statement about nature that is ALWAYS

TRUE– EX: Law of Biogenesis, Laws of Gravity

Review of terminology

Levels of Organization in Living ThingsMoleculesMolecules

↓↓CellsCells

↓↓TissuesTissues

↓↓OrgansOrgans

↓↓SystemsSystems

↓↓OrganismsOrganisms

↓↓PopulationsPopulations

↓↓CommunitiesCommunities

↓↓EcosystemsEcosystems

↓↓BiosphereBiosphere