Transcript Biology Notes on Section 1-1 ( Questions) 1. What is

What is science? What is its goal?
Its goal is to investigate and understand nature,
explain the events in nature and make predictions.
2. How is science different from other fields of study?
Science differs from other fields by dealing with the
natural world, organizing info, and testing
explanations.
Igor
Mystery Box- What is in my box?
How would you find out?
What questions could you ask?
Can you figure out the answer without seeing
inside the box? Explain.
Does this happen in our lives or in science?
Senses - can be used to make inferences.
What are inferences? (logical interpretation)
How can you use your 5 senses to do this?
Sticky table-What can you infer?
Car alarm - ???
Water running down the window
Smell pizza??
The milk tastes bad???
How Scientists Work 1-2
Scientific method
Main Steps:
1. Observe, question, problem
2. research
3. Hypothesis
4. Controlled experiment/ data
5. Conclusion
-Who is a scientist? What do they do?
Controlled experiments contain variables.
Types of variables:
Manipulated (experimental)
Responding (results or outcome)
Controlled (same in all trials of experiment)
Only one manipulated variable can be changed per experiment.
Brainstorm: Design an Experiment to test the presence of bacteria
on remote controls.
Section 1-1
Observation and Inference
Statement
Object A is round and orange.
Observation Inference
X
Object A is a basketball.
Object C is round and black and white.
X
Object C is larger than Object B.
X
Object B is smooth.
X
X
Object B is a table-tennis ball.
Each object is used in a different sport.
Go to
Section:
Object A is
X
X
X
a
basketball.
Object B is a
table-tennis
ball.
Object C is a
soccer ball.
Flowchart
Section 1-2
Designing an Experiment
State the Problem
Analyze Results
Form a Hypothesis
Draw a Conclusion
Set Up a Controlled Experiment
Publish Results
Record Results
Go to
Section:
What is a hypothesis? Can you prove it?
What is a theory? Can you prove it?
It is a well-tested explanation. (evolution)
Can a theory come from a hypothesis?
What is a law?
It is an explanation or theory has been tested and re-tested and is accepted
as true. (gravity)
-Laws can be changed and help explain nature.
*How to study science:
1. Don’t memorize
2. Understand concepts and apply
3. Group items
4. Consider structure and function
5. Think critically and problem solve
6. Be aware of the world around you (observe and listen!)
Spontaneous Generation
Can Life come from non-life? Explain. Does a bull produce
bees or does manure produce beetles?
Definition spontaneous –unexpectedly
generate-bring into existence
Redi - His tests proved flies do not come from rotting meat.
What was his hypothesis?
What variable did he change?
Needham – What can you learn from him?
What was Needham’s hypothesis?
Spallanzani – What did he do?
What was his hypothesis? What was the manipulated
variable?
Figure 1-8 Redi’s Experiment
on Spontaneous Generation
Section 1-2
OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat.
HYPOTHESIS: Flies produce maggots.
PROCEDURE
Uncovered jars
Controlled Variables:
jars, type of meat,
location, temperature,
time
Covered jars
Several
days pass
Manipulated Variables:
gauze covering that
keeps flies away from
meat
Responding Variable:
whether maggots
Maggots appear
No maggots appear
appear
CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous
generation of maggots did not occur.
Figure 1-10 Spallanzani’s
Experiment
Gravy is boiled.
Gravy is boiled.
Flask is
open.
Flask is
sealed.
Gravy is teeming
with
microorganisms.
Gravy is free of
microorganisms.
Figure 1-11 Pasteur’s
Experiment
Broth is boiled.
Broth is free of
microorganisms
for a year.
Curved neck
is removed.
Broth is
teeming with
microorganisms.
Biology as a Science
Section 1-3
What are the characteristics which distinguish life from non-life?
Characteristics of life-All living things:
1.
2.
3.
4.
5.
6.
7.
8.
Reproduce
Contain one or more cells
Grow/develop
Use energy
Respond to the environment
Change over time (evolve)
Universal genetic code(DNA or RNA)
Stable internal environment (homeostasis)
*Must everything reproduce to be alive? Why is it important to
continuing life?
*How do organisms get energy?
*What are some things for which organisms use energy?
*How do you respond to your environment? How do you get energy?
Metabolism - chemical reactions needed to carry out life processes.
What is diversity? Is life diverse?
Are all organisms unicellular? Multicellular?
What is the biggest cell?
Hint: ostrich’s lay these.
* Sexual Vs. Asexual reproduction What are these?
*How is growth different from development (caterpillar, human)
*Do all organisms grow at the same rate?
*Response to the environmentHow do ants survive? Why?? Name ways you respond to your
environment.
What is homeostasis?
Homeostasis - tries to maintain balance inside the organism even under
changing conditions.
* What happens to humans when we lose too much fluid on a hot day?
*What processes help us maintain homeostasis?
Characteristics of Living Things
Characteristic
Examples
Living things are made up of units called
cells.
Living things reproduce.
Living things obtain and use materials and
energy.
Many microorganisms consist of only a single cell.
Animals and trees are multicellular.
Maple trees reproduce sexually. A hydra can
reproduce asexually by budding.
Flies produce flies. Dogs produce dogs. Seeds from
maple trees produce maple trees.
Flies begin life as eggs, then become maggots, and
then become adult flies.
Plants obtain their energy from sunlight. Animals
obtain their energy from the food they eat.
Living things respond to their environment.
Leaves and stems of plants grow toward light.
Living things maintain a stable internal
environment.
Despite changes in the temperature of the
environment, a robin maintains a constant body
temperature.
Taken as a group, living things change
over time.
Plants that live in the desert survive because they have
become adapted to the conditions of the desert.
Living things are based on a universal
genetic code.
Living things grow and develop.
Name some branches of biology.
What do they do?
(Ecology, zoology, cytology, embryology, microbiology.)
Why do scientists work together?
Ex: Would a scientist need to talk with a molecular biologist when formulating
contact lens solution? Do they need to talk to chemists? Doctors? Why?
Do ecologists need to know about both plants and animals? Why?
Organization Levels:
1. Molecule
2. Cells
3. Tissue
4. Organ
5. Organ System
6. Organism
7. Population
8. Community
9. Ecosystem
10.Biosphere
Why is the earth sometimes called a spaceship? How can applying biology
make you more likely to protect the environment?
Figure 1-21 Levels of Organization
Biosphere
The part of Earth
that contains all
ecosystems
Biosphere
Ecosystem Community and
its nonliving
surroundings
Hawk, snake, bison, prairie dog, grass, stream, rocks, air
Community Populations that
live together in a
defined area
Hawk, snake, bison, prairie dog, grass
Population
Group of
organisms of one
type that live in
the same area
Bison herd
Section 1-3
Figure 1-21 Levels of
Organization continued
Organism Individual living
thing
Bison
Tissues, organs,
Groups of and organ systems
Cells
Brain
Nervous tissue
Cells
Nervous system
Smallest functional
unit of life
Nerve cell
Groups of atoms;
smallest unit of
Molecules most chemical
compounds
Go to
Section:
Water
DNA
Section 1-4 Tools of Biologists
1. Compound light microscope
2. Electron microscopes (transmission electron microscope and
scanning electron microscope)
3. Fractionation - breaks apart cell parts like a blender.
4. Centrifugation- separates cell parts by spinning.
5. Microdissection - small parts can be removed using special tools
6. Cell cultures - nutrient agar (gel) grows the cells in a petri dish.
Historical note: DaVinci - suggested the use of a magnifying lens, yet
it took over 50 years before reports of the new invention were published.
Why did it take so long?
Who was Alexander Flemming?
Metric System
Why is the metric system universal? Based on 10.
Meter - (length)was first introduced in 1791 in France. It equaled
1/10,000,000 of the distance from the equator to the north pole. In 1983- it
was defined as the length the light traveled during 1/299,792,458 of a
second.
-Celsius - (temperature) devised by Anders Celsius
( 1701-1744). 0 degrees is the melting point of ice and 100 degrees is the
boiling point of water. Also called
centigrade. This scale is based on 10.
-Liter (volume)
-Gram (mass) -What is the difference between mass and weight?
-Seconds (time) use prefixes for very small or large #’s.
-Light-year (distance) Unit used only for very large
distances (space). This is the distance light travels in one year. The speed
of light is 3 x 108 m/s.
Measure using what unit?
1. Glass of milk _________________ (volume)
2. Pack of gum _________________ (mass)
3. Length of a Porsche ___________ (length)
4. Width of a paperclip __________ (length)
5. Pack of M & M’s ____________ (mass)
6. Bottle of water _______________ (volume)
7. Body temperature of a lizard __________ (temp)
8. Diameter of the sun _________________ (length)
9. Distance to Pluto? __________________ (distance)
10. How late you are for class ___________ (time)
Metric Prefixes
KiloHectoDecameter, gram, liter
DeciCentiMilli-
Measuring length
• Use a ruler
• Line up from zero not the end of the ruler
• Small divisions are millimeters
0
1
2
3
4
Volume
• Liter a common unit
• 1 L about 1/4 of a gallon - a quart
• 1 mL is about 20 drops of water or 1 sugar
cube
Measuring Volume
30
• Use a graduated cylinder.
• The water will curve in
the cylinder.
• Hold it level with your
eye.
• Read the bottom of the
curve.
• Measures in milliliters
mL.
20
10
Mass
• weight is a force, mass is the amount of
matter.
• 1gram is defined as the mass of 1 cm3 of
water at 4 ºC.
• 1 kg = 1 L of water
• 1 kg = 2.2 lbs
• 1 g = 1 paper clip
• 1 mg = 10 grains of salt or 2 drops of water.
Measuring Mass
•
•
•
•
•
Use a triple beam balance
First balance it at zero.
Then put item on
Then move one weight at a time
When balanced, add up the weights
0
10
20
0
0
1
30
40
100
2
3
50
200
4
60
70
300
5
6
7
80
90 100
400
500
8
9
10
Tables
• Organizing data into groups
• Putting those groups into rows and columns
• Gives us an easy way to compare data
Graphs include
• A title
• Labeled axes
• A consistent scale.
Graphs
• Give a visual representation of data
• Summarizes data.
• Two types of variables
– Independent variable the thing you have control
over { x-axis }
– Dependent variable the thing that you don’t have
control over (What you measure). { y-axis }
• Three types of graphs line, bar, and circle
Making a Graph From A Data Table
Time
Absorbed
by Roots
(g/h)
Released
by Leaves
(g/h)
8 AM
10 AM
12 PM
2 PM
4 PM
6 PM
8 PM
1
1
4
6
9
14
10
2
5
12
17
16
10
3
Relative Rates (g/h)
Water Released and Absorbed by Tree
20
Water released by leaves
15
10
5
Water released by leaves
0
8 AM 10 AM 12 PM 2 PM 4 PM 6 PM 8 PM
Time
Circle Graphs
• Often called a pie 42%
chart
• divided into parts
• easy to compare to
whole amount.
• Use several to show
changes over time
33%
25%
Buildings
Transportation
Industrial
Bar Graphs
• Bar Graphs- wide
columns used
things like weight,
height , and length.
• Compare quantities
12
10
8
6
4
2
0
Production of Energy per
gram
Carbohydrates
Proteins
Fats
Line Graphs
• Line Graphs- compares sets of data, show
change and patterns over time.
Line Graphs
• Line Graphs- compares sets of data, show
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change and patterns over time.
30
25
New York
San Diego
Salina Cruz
20
15
10
5
0
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Chapter 1
The Study of Life
1.3 Methods of Science
Analyze the Data
 A graph of the data
makes the pattern
easier to grasp.
 Even when a
hypothesis has
not been
supported, it is
valuable.