Biology I – S409Chapter 1 NotesThe Study of Life

1

Name: Hour: Date:

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 about with the environment, they are learning about biology. A person who studies living things is biology. A person who studies living things is referred to as a biologist. referred to as a biologist. 22

T: 2

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)

33

T: 2Scientists are: Observant, Skeptical, Curious and Open-minded!

Characteristics of Life

1. Made of CELLS: unicellular / multi-cellular

2. Are ORGANIZED (cells make up tissues…)

3. GROW and DEVELOP

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

5. RESPOND to stimuli: either internal or external (migrate)

6. Require ENERGY

7. Maintain HOMEOSTASIS: a stable internal environment

8. ADAPTATIONS/EVOLVE over time-occurs in populations, NOT individual organismsCharacteristics of Life

44

T: 2, 7

Levels of Organization in Living Things(#2 on previous slide)

MoleculesMolecules↓↓

CellsCells↓↓

TissuesTissues↓↓

OrgansOrgans↓↓

SystemsSystems↓↓

OrganismsOrganisms↓↓

PopulationsPopulations↓↓

CommunitiesCommunities↓↓

EcosystemsEcosystems↓↓

BiosphereBiosphere

Organization of an

organism

Ecological Organizatio

n

55

T: 8

Concept CheckConcept Check1. If something reproduces asexually

(for example: a starfish growing a new arm after being broken off by a predator or a broken vine landing in soil and starting to grow into a new plant) is it still considered to be a living thing?– Yes or No – Yes! Though not all living things reproduce asexually, it

is still a form of reproduction

2. Is the ability to breathe a characteristic of life?– Yes or No– NO! Though some living things do breathe (animals)

there are other living things that do not (bacteria, plants, fungus)

66

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

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

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

substances– EX: mice spontaneously appear in stored grain or

maggots spontaneously appear in meat

10

77

T: 2

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:

8

T: 2

*Biogenesis: living things only come from other living things as a result of reproduction

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)

9

T: 16

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 1010

Science is the body of knowledge based on the study of nature; which leads to the development of

explanations. Scientific explanations combine consist evidence gathered from many observations and

experiments.

THEORY–Explanation that has been tested and –not yet disproved (several experiments)–EX: Theory of Evolution, Cell Theory

LAW–Statement about nature that is ALWAYS TRUE–EX: Law of Biogenesis

Theory vs. Law

1111

T: 5

Concept CheckConcept Check1. In science, is it acceptable to use measurements such

as inch or foot?– Yes or No – NO! In science it is considered proper to use the SI

measurement system with the corresponding prefix. Length: meter Volume: liter Mass: gram

2. If you have enough experimental data to support a hypothesis, is that a law or a theory?– Theory; something that has not yet been disproved;

has extensive evidence and allows for making accurate predictions

1212

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, used to explain

observations– Collect Data/Background information when

necessary

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

Section 3: Methods of Section 3: Methods of ScienceScience

1313

T: 1, 4, 14

3. Collect the Data Controlled Experiments have experimental and control groups

– Control groups: used for comparison– Experimental groups: the group exposed to the factor being tested

The “independent” variable; the factor that changes; the thing that is being tested; only use 1 at a time (everything else in the experiment should be kept constant)

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

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

1414

T: 3, 4, 6

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

– Bar Graph: used to compare different groups or track things over time– Line Graph: used to track changes over time (connect the dots)– X-Y Scatter Plot: line of best fit (average)– Table: used to display data in an organized way– Chart (Pie): used to compare parts of a whole (%)

5. Report or Form Conclusions• Accept or reject your hypothesis based on the data collected

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

NAMENAME TIMETIME

FrankFrank 33 sec33 sec

JessicaJessica 27 sec27 sec

1515

T: 3, 4, 13

Tools of a Biologist: The Microscope Compound Light Microscope

– uses light reflected by two or more lenses– 1 eyepiece, 1 light (light passes through)– Used to view small specimens (alive or preserved)

Stereoscope (AKA Dissecting Microscope)– 2 eyepieces, 3 light combos (3-D objects)– Used to view larger specimens (alive or preserved)

Electron Microscope– Uses electrons reflected by magnets– Can only be used with non-living specimens– Two types (SEM & TEM)

* We will use the CLM & Stereoscope in Bio I 1616

T: 9

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

17

T: 9

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! 18

T: 10, 12, 15

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

19

Concept Check1. What type of microscope will we use in our

classroom this year? Compound Light Microscope, Stereoscope, Electron

Microscope Both the Compound Light Microscope and the

Stereoscope

2. Which type of graph, table or chart is used to track data over time? Bar, Line, X-Y, table, pie A line graph is most commonly used to track data

over time; a bar graph may also be used. It is important to pay attention to the type of data you have collected in order to best represent your findings!

20