Chapter 1 Review
What are the 7 characteristics of life?
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Metabolism
Reproduction
Sense and respond to change
Change through time (evolution)
Homeostasis
Organization and cells
Growth and development
Define organization.
• Order within an organism
• Can be internal or external
List the levels of organization
beginning with atoms.
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Atoms
Biological molecules
Cellular organelles
Cells ***
Tissues
Organs
Organ systems
Organism (multicellular)
What is a cell? Is the “stuff” inside of a
cell living? Why or why not?
• Smallest unit that can perform all life
processes
• NO! The cell is the smallest unit of life!
Define stimulus.
• Change
• Can be internal or external
Explain what is meant by “response to
stimuli.”
• Organisms can react to changes in their
environments
What is homeostasis? Give an
example.
• stability
• All living organisms have ways to maintain a
stable internal environment in changing
external conditions
• Exp. Sweating to maintain body temperature
In the following situation, identify the
stimulus and the response.
• A paramedic shines a pen light into a patient’s
eyes. The patient’s pupils get smaller.
• stimulus = light
• response = pupils constrict
What is metabolism?
• The sum of all chemical reactions that take in
and transform energy and materials from the
environment
What are the two types of metabolism?
What’s the difference between the two?
• Anabolism – building larger products
• Catabolism – breaking down larger molecules
into smaller ones for raw materials
Condensation and hydrolysis: which
reaction is anabolic and which is catabolic?
• Condensation joins small subunits called
monomers to form large molecules called
polymers so it’s __________!
anabolic
• Hydrolysis uses water to break polymers into
monomers so it’s ___________!
catabolic
How does growth occur in organisms?
• Cell division
• Cell enlargement
Multicellular organisms also develop. What is
development? How do organisms develop?
• Development = process by which organisms
become mature adults
• Cell differentiation – act of cells becoming
different from one another
• Cell specialization – cells perform special and
specific jobs
What is reproduction?
• to produce new organisms
• essential for survival of the species but not of
an individual
• Important for transmitting hereditary info.
encoded in DNA to next generation
Segments of DNA with instructions for
a single protein/trait are called _____.
• Genes!
Differentiate asexual and sexual
reproduction.
• Sexual
– Two parents
– Offspring are similar to
parents but not
identical; they’re a
combination of both
parents’ traits
• Asexual
– One parent
– Offspring are genetically
identical to parent
What is evolution and how does it
occur?
• Descent with modification i.e. populations
change through time
• Occurs by natural selection
– Organisms within a population with more
favorable traits are better able to survive and
reproduce thus passing those traits on
What are three recurring themes in
biology?
• Unity and diversity of life
• Interdependences
• Evolution
What is the scientific method?
• Organized approach to science
On what two principles is this method
based?
• Events in the natural world have natural
causes
• Uniformity
What is the first step of the scientific
method?
• Observation
• How are observations made?
– All 5 senses
• Observations lead to _______________
– questions!
The next step is hypothesize. What is
a hypothesis?
• A probably explanation/solution to your
question
• Should it be testable?
– Yes!
• Can we prove a hypothesis?
– No! We can only accept (or reject) it.
Once we have a hypothesis we can make a
prediction. What’s a prediction?
• A forecast of what we think will happen if the
hypothesis is true.
Scientists will then conduct an experiment.
What is a controlled experiment?
• An experiment that compares groups with
only one variable changing between them
List and explain the parts of a
controlled experiment.
• Control = standard group for comparison
purposes
• Experimental groups = identical to control
except for one factor or variable
• Independent variable = manipulated variable
• Dependent variable = responding variable
Determine the control, experimental
groups, the I.V. and the D.V.
• A shopping mall wanted to determine whether the
more expensive “Tough Stuff” floor wax was better
then the cheaper “Steel Seal” floor wax at protecting
its floor tiles against scratches. One liter of each
brand of floor wax was applied to each of 5 test
sections of the main hall of the mall. The test
sections were all the same size and were covered
with the same kind of tiles. Five (5) other test
sections received no wax. After 3 weeks, the number
of scratches in each of the test sections was
counted.
What are two ways scientists can
eliminate bias?
• Blind experiments
• Repeat experiments
Scientists can collect two types of data.
What are they? What’s the difference?
Give an example of each.
Qualitative
descriptions; data is
observed not
measured
colors, textures,
smells, tastes,
appearances, beauty,
etc.
Quantitative
deals with numbers; data
can be measured
length, height, area,
volume, width, speed, time,
temperature, humidity,
sound levels, cost,
members, ages, etc.
After data collection and analysis,
what step comes next?
• Draw a conclusion/make inferences
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The last step is communication. What are
some ways scientists communicate
research and results?
Research teams
Joint meetings and symposiums
Publish research in journals
Peer reviews