Transcript Unit One “Science Introduction and Cellular Function”

Unit One
“Science Introduction and
Cellular Function”
Chapter One
“The Science of Biology”
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All life on Earth is subdivided into groups based
on similar structure and function
The largest group into which organisms are
placed is a “Kingdom”
There are six kingdoms (previously there were
five)
A Kingdom is the broadest group by which
organisms are categorized
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Further subdivisions of organisms are done as
follows:
Kingdom (King)
Phylum
(Philip)
Class
(Came)
Order
(Over)
Family
(From)
Genus
(Great)
Species
(Spain)
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There are six Kingdoms:
Archaea - Methanococcus
 Bacteria – Lactobacillus (rod-shaped)
 Protista – Giardia (intestinal parasite)
 Fungi – Mushrooms
 Plantae – Oak tree/Rose bush
 Animalia - Black Bear/Alligator
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Prokaryotic (single celled)
Similar to Bacteria
Have a type of protein that Bacteria do not
possess
Have been in existence for billions of years:
“since the beginning”
Some Archaea species are Extremophiles: live
in salty, acidic, or high temperature
environments
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Prokaryotic – single celled organisms
Similar to Kingdom Archaea
They are one of three shapes: spherical, rod, or
spiral
Most bacteria are heterotrophic (cannot make
their own food) and divide through fission
Bacteria fix nitrogen which is important in
reference to nutrient content of the soil
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Can be either Prokaryotic or Eukaryotic
Simplest of the Eukaryotes
Can be either Heterotrophic or Autotrophic
This is the kingdom where species are
categorized when they do not fit into any other
kingdom
Prokaryotic Amoeba and Eukaryotic Sea Kelp
are both members of this kingdom
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Heterotrophic organisms
Eukaryotic organisms
Digest their food externally
Mushrooms = Fungi
“Mycology” = study of fungus
Sessile organisms
Reproduce through spores both sexually and
asexually
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Autotrophs – they convert carbon dioxide to
oxygen via Photosynthesis
Essentially, they make their own food =
Producers
Sessile organisms
All life depends on plants - they are at the
bottom of the food chain
Plant cells contain chlorophyll which allows
them to photosynthesize
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Heterotrophs
Wide variety of species based on varying
structure and function
Invertebrate or Vertebrate
Insects, Jellyfish, Fish, Amphibians, Reptiles,
Birds, Mammals
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Structure and Function - what is it composed of,
and how does it work
Energy and Metabolism – consumption and
conversion of food into usable energy
Homeostasis – maintenance of bodily function
throughout changes in environmental conditions
Growth and Reproduction – maturity of juvenile,
then subsequent reproduction to perpetuate species
Heredity – passage of physical traits through
reproduction
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Atoms – Molecules/Compounds – Organelles –
Cells – Organs – Organ Systems – Organism –
Population – Community – Ecosystems –
Biomes – Earth!
Organization proceeds from smallest to largest
Very small structures combine to form an
organisms that then interact to create a living
Earth, which can be thought of as a “super
organism”
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Deductive Reasoning – using what you know to
make decisions and learn new information
Inductive Reasoning – using careful
observations to learn new information
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Hypothesis – an educated guess
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In order to learn new information about the world
and how it works, scientists employ the Scientific
Method:
1. State the problem
2. Formulate a hypothesis
3. Experiment
4. Record data
5. Make a conclusion
*** These five steps may be repeated several times in
reference to a specific initial hypothesis
Control - A standard of comparison for checking or
verifying the results of an experiment; an individual
or group used as a standard of comparison
 Variable – factor in an experiment that is
manipulated by the scientist
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two types: independent and dependent variables
http://www.biologycorner.com/worksheets/controls.
html
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In order for scientists to be credible when
presenting their results to the rest of the world,
it is imperative they be objective.
Reporting one’s results by way of numbers is the
best way to remain objective: a 1 is a 1 no matter
who reviews the data.
Objective = Numbers = Facts
Subjective = Words/Pictures = Opinion
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A lab report should always have data displayed
in table form (rows and columns), then
subsequently displayed in graph form
The graph clearly shows the presence or absence
of any relationship between the variables used in
the experiment
There are three commonly used graphs that
display scientific data: Line, Bar, and Pie
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A Line Graph is used to show change of a
factor over time
Time, the independent variable, is plotted on the
X axis
The other factor, which is the dependent
variable, is plotted on the Y axis
http://www.mcwdn.org/Graphs/Line2FW.gif
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A Bar Graph is used to show how a factor
changes over time, but not at a continuous rate
as does the Line Graph
Time, the independent variable, is plotted on the
X axis
The other factor, which is the dependent
variable, is plotted on the Y axis
http://www.myleague.com/graphs/bar_graph_
3d.gif
Pie Graphs are used to show parts of a whole
http://www.helixcharter.net/department_sites/so
cialscience/honors_geo/student%20work/per1
%20websites/T1jbetheawp/images/pie.gif
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The purpose for employing the Scientific
Method to conduct experiments is to learn new
information
As more and more information is gathered
about a topic, the more certainty there is as to
how the topic functions
Eventually, when there is agreement among all
of those in the scientific community, the topic is
recognized as a fact
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A new idea that is just being tested = Hypothesis
An idea that has been tested many times, and each time
the results support the idea = Theory
A statement of scientific fact = Law
“I will save a $100 or more on my electric bill if I install
a solar energy system” Hypothesis
“The speed of light within a vacuum is the same no
matter the speed at which an observer travels ”
Theory
“An object will tend to stay at rest unless acted upon by
another object” Law
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The Cell Theory: Cells and Organelles (Hooke)
The Gene Theory: DNA and RNA (Watson and
Crick)
The Theory of Heredity: Chromosomes and
Traits (Mendel)
The Theory of Evolution: Evolution, Natural
Selection, and Adaptation (Darwin)