Transcript Chapter 1

Chapter 1
Biology: Science of Life
What is Science?
• A verifiable process – must be testable!
• Evidenciary
• Collaborative
• Constantly questioning the known, the unknown,
and each other
• Looking for, and trying to solve problems
Overview
Experimental Design recap
• Control/ Control group: comparative group; the usual
conditions
• Experimental group: tested group; alter one
condition to compare to control group
• Independent variable: altered factor, manipulated
variable
• Dependent variable: measured factor, responding
varibale, data collected
• Constant: unchanged factor(s), controlled variables
Analyze and represent data
Biology: Science of Life
• Study past, present and future life
– Interactions
– Structures
– Functions
• Solve biological problems
– Agriculture
– Disease
– Conservation/Remediation
What is life?
We decide:
• 1+ cells
• Organization
• Grow/develop
• Reproduce
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Respond to Stimuli
Use Energy
Homeostasis
Adapt/Genetics
Life Traits I
• 1+ cells
– The cell is the basic unit of life
• What does basic unit mean?
• Organization
– Atoms->molecules->cells->tissues->organs->organ systems>organism (assuming multicellular)
• How do we amend this sequence if the organism is
unicellular?
• Grow/develop
– Increase cell size and/or increase cell number
– Go through stages of maturity
• Homeostasis
– Regulate internal conditions Ex: temp, water, blood sugar
• Reproduce
Life Traits II
– Species = group of organisms that can interbreed to
produce viable (fertile) offspring
• Respond to Stimuli
– Able to process and react to internal/external environ.
• Use Energy
– Get/make food (chemical energy) to fuel metabolism,
get energy (ATP) to power processes
• Adapt/Genetics
– Change in inherited traits over time
• Cells:
Details on Characteristics
Unicellular
Multicellular
1st life forms
Evolved later
1 cell
More than one cell
All bacteria, all protists
All animals, all plants,
(euglena, ameboa,
some fungi
paramecium), some fungi
GROW by cell
enlargement only
REPRODUCE by cell
division (asexual
reproduction)
GROW by cell
enlargement and cell
division
REPRODUCE mainly by
making specialized cells
that combine sexually
• REPRODUCTION:
Details on Characteristics II
Asexual
Evolved first
Sexual
Evolved later
Unicellular organisms
divide to make more
identical unicellulars
One “parent” –
contributes 100% of
genetic info
Make a clone – no genetic
variation between
generations
Multicellular organisms
use meiosis to make
sperm/egg
Two “parents” – each
contribute 50% of genetic
info
Genetically different
offspring – more variation
in population – GOOD for
survivability/evolution
More on Reproduction…
• Bacteria (unicellular, asexual) can
exchange genetic info between
individuals to increase genetic variation
– Called “conjugation”
– Remember: genetic
variability is a good thing for
evolutionary survival!!
• Adaptation/Response
Details on Characteristics III
Adaptation (evolution) Response (to stimuli)
Long-term
Short-term
Population response to
changing environmental
conditions
More genetic variability
in the population = the
better able the
population can adapt
EX: adaption as a result
of changing climate –
thicker fur
Immediate feedback to
stimuli
EX: response to changing
temperatures – burrow,
put on a coat
• Energy use
Details on Characteristics III
Autotrophs
Heterotrophs
BOTH versions of organisms convert “food” energy
into ATP energy to power their cellular processes!!
All plants, some
All animals, All fungi, some
bacteria, some
bacteria, some protists (NOTE:
protists
some plants can do this too!
“carnivorous plants –VFT!)
AKA “producers”
AKA “consumers”
Make own food
Eat other organisms or the
products of other organisms
Two versions:
• Photosynthesis
• Chemosynthesis
More on Autotrophy…
There are two general processes:
•Photosynthesis
ouse sun as energy needed to make food
•Chemosynthesis
ouse chemicals as energy
oHydrothermal deep sea vents
Life vs. Viruses
• Bacteria, protists, fungi, plants and animals are
living; viruses are NOT
• living things have ALL characteristics of life, viruses
do not exhibit all
• NOTE: anything you need a microscope to see is
called a “microbe”, anything that causes disease is
called a “pathogen”.
– MOST bacteria do not cause human illness!!
Viruses:
 are acellular
 do not (generally) reproduce themselves
 do not use energy/ have a metabolism
Chapter 1
The Study of Life
1.1 Formative Questions
What is the process of change that takes
place during the life of an organism?
A
2.
B
3.
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4.
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D
A. adaptation
B. development
C. growth
D. maturation
Chapter 1
The Study of Life
1.1 Formative Questions
Some species of plants begin opening their
flowers in the morning when they are exposed
to sunlight. What characteristic of living things
does this represent?
1.
A
2.
B
3.
C
4.
D
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D
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A. acquiring energy
B. adapting to the
environment
C. displaying organization
D. responding to stimuli
Chapter 1
The Study of Life
1.1 Formative Questions
What process regulates an organism’s internal
conditions and keeps them stable?
A
2.
B
3.
C
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D
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A. adaptation
B. equilibrium
C. homeostasis
D. metabolism
Chapter 1
The Study of Life
1.2 Formative Questions
What is a theory?
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2.
B
3.
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4.
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A. a body of knowledge
about a natural phenomenon
B. a creative tool for
designing investigations
C. a scientific inquiry that
seeks to provide
an explanation
D. an explanation supported
by observations
and experiments
Chapter 1
The Study of Life
1.2 Formative Questions
Scientists discard
observations and data
that are not consistent
with current scientific
understanding.
A
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A
2.
B
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B
A. true
B. false
1.
Chapter 1
The Study of Life
1.2 Formative Questions
A scientist wants to report the findings from
her investigations. Before her information
can be published, what must it go through?
A
2.
B
3.
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A. forensics
B. peer review
C. scientific methods
D. the metric system
Scientific Theory
• Explains natural phenomenon
• Supported by observations/experiments
• Always same results
– Not a hypothesis
– Can be modified or discarded by NEW info
– Ex. Gravity, cells, tectonic plates
Chapter 1
The Study of Life
1.3 Formative Questions
When you form a logical conclusion
based on your observations and what you
already know, what are you making?
A
2.
B
3.
C
4.
D
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D
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A. a conjecture
B. an inference
C. a speculation
D. a theory
Chapter 1
The Study of Life
1.3 Formative Questions
What is a hypothesis?
2.
B
3.
C
4.
D
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D
A
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B
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A. a defined question
B. a curious assumption
C. a tested inference
D. a testable explanation
Chapter 1
The Study of Life
1.3 Formative Questions
What type of discovery is a serendipitous
discovery?
A
2.
B
3.
C
4.
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A. accidental
B. anticipated
C. ingenious
D. whimsical
Chapter 1
The Study of Life
Chapter Diagnostic
Questions
Why is the metric system preferred by
scientists?
Answer: Using the same system of
measurements allows a scientist
to repeat another’s work
knowing
that he or she is performing the
experiments exactly the same.
Chapter 1
The Study of Life
Chapter Diagnostic
Questions
What is a testable explanation?
2.
B
3.
C
4.
D
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D
A
C
A
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1.
B
A. observation
B. hypothesis
C. experiment
D. constant
Chapter 1
The Study of Life
Chapter Diagnostic
Questions
Which is not a characteristic of all
organisms?
1.
A
2.
B
3.
C
4.
D
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A. made of one or
more cells
B. grows and develops
C. capable of
rational thought
D. maintains
homeostasis
Chapter 1
The Study of Life
Chapter Assessment
Questions
Identify the term used to describe an
explanation of a natural phenomenon
supported by observation and
experimentation.
B
3.
C
4.
D
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2.
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A
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C
A. forensics
B. natural law
C. theory
D. physics
1.
Chapter 1
The Study of Life
Chapter Assessment
Questions
In a controlled experiment, which factor is
changed by the experimenter?
2.
B
3.
C
4.
D
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D
A
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B
A
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1.
C
A. control group
B. experimental group
C. dependent variable
D. independent variable
Chapter 1
The Study of Life
Chapter Assessment
Questions
Look at the figure below. Why is scientific
data often displayed in graphs?
Chapter 1
The Study of Life
Chapter Assessment
Questions
Answer: Graphs help show patterns in the
data and make it easier to
understand.
Chapter 1
The Study of Life
Standardized Test
Practice
Which is the
dependent variable
in this experiment?
A. mass
B. number
of days
0%
B
A
0%
1.
A
2.
B
Chapter 1
The Study of Life
Standardized Test
Practice
Which biological science was Jane Goodall
studying when she observed chimpanzees?
A
2.
B
3.
C
4.
D
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B
A
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1.
C
A. ecology
B. genetics
C. animal behavior
D. biotechnology
Chapter 1
The Study of Life
Standardized Test
Practice
In which activity would an environmental
biologist most likely be involved?
A
2.
B
3.
C
4.
D
C
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D
1.
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B
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A
A. genetically
engineering plants
B. finding ways to
protect species
C. preventing the spread
of disease
D. developing new
medicines and vaccines
Chapter 1
The Study of Life
Standardized Test
Practice
Which is an indication that an idea is based on
pseudoscience?
A
2.
B
3.
C
4.
D
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1.
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B
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A
A. It brings up
more questions.
B. It causes disagreement
and debate.
C. It does not welcome
scientific investigation.
D. It does not receive
acceptance by scientists.
Chapter 1
The Study of Life
Standardized Test
Practice
Scientists use laboratory rats to test the
effects of a new drug, Razatrin. What do rats
in the control group receive?
A. food containing Razatrin
B. food without Razatrin
C. food containing
another drug
D. food containing a variety
of drugs
E.No food
1.
A
2.
B
3.
C
4.
D
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B
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D