Biology & You

1.1 - The Nature of Science
Science is the search for knowledge about the universe around us.  It requires us to make observations and to draw conclusions based on our observations.  It also requires us to be willing to change our views as new information is gained.

Scientific Thinking...
  ...requires skepticism (show me the evidence!)
  ...must be open to change governed by universal laws (truths that are valid everywhere
     in the universe)
  ...requires ethical behavior, such as...
     ...reporting accurate information
     ...allowing peers to review one's work
     ...obeying the law
     ...making sure that no one is coerced, exploited, or involuntarily
        exposed to danger

1.2 - The Scientific Method
The Scientific Method
1. State the Problem.
2. Background Research and initial Observations.
      -observation: using the senses to perceive objects or events
3. Make a Hypothesis.
      -hypothesis: a possible explanation that can be tested
4. Test the Hyposthesis with an Experiment.
      -experiment: a procedure carred out under controlled conditions to
                             test a hypothesis.

  a. Control Group: a standard for comparison, the control group
         receives no experimental treatment.
  b. Experimental Group: same as the control group, but with
         one variable that has been changed.
         -The variable being changed is the independant variable.
         -Variables that change in response to the independant
             variable are dependant variables.
5. Analyze the Data.
6. Make a Conclusion based on the data.
7. Verify your Results by comparing with research done by others.

A theory is a general explanation for a broad range of data, which has been supported by many experiments.

Data is information that you gather by making observations.  There are two main types of data:
 - Quantitative data involves numbers, usually measuring or
 - Qualitative data invovles describing the quality or
    characteristics of something, usually without numbers.

1.3 - Tools & Techniques
The Metric System is a way of measuring things that is used around the world.  It is a "base 10" system - which means that each unit is 10 times larger than the previous one.  There are 10 millimeters in a centimeter, 10 centimeters in a decimeter, and 10 decimeters in a meter.  (In the English system, there are 12 inches in a foot, 3 feet in a yard, and 1,760 yards in a mile!)

The Metric System uses base units to determine what type of measurement you are making.  Some common base units, and their dimensions, are:
   Meter (m) - base unit for length.
   Gram (g) - base unit for mass.
   Liter (L) - base unit for volume.
   Degree Celsius (C) - base unit for temperature.

Length is used to tell how far it is between two points.
Mass is used to tell how much material is in an object.
Volume is used to tell how much space an object takes up.
Temperature is used to tell how much heat an object has.

In Biology, we will mainly be working with the following prefixes:

Base Unit = Meter (m)
   1,000 Meters = 1 Kilometer (km)
   1/100 of a Meter = 1 Centimeter (cm)
   1/1,000 of a Meter = 1 Millimeter (mm)

There are 1,000 millimeters in a meter because 1 millimeter is 1/1,000 of a meter.

Microscopy is the use of microscopes to view objects that are very small.  The two types of microscopes are light microscopes (which use light to view objects) and electron microscopes (which use beams of electrons to make an image of an object on a computer screen).

Sterile technique is a method of keeping unwanted microbes out of the lab area, or off of tools.  This is especially important if you are trying to work with a certain sample of bacteria that you do not want contaminated by the natural bacteria that lives on and around us.

Safety is important, as scientists can be exposed to dangers such as chemical burns, exposure to radiation, animal bites, or poisonous plants.  Important safety guidlines for lab work include...
 - Listen carefully to the teacher and follow all directions.
 - Read your lab procedure carefully before beginning the lab.
 - Do not take any shortcuts in your lab procedure.
 - Always wear protective clothing in the lab, such as safety
   goggles and lab aprons or any other appropriate gear.
 - Measure chemicals precisely.
 - Never taste or smell any materials or chemicals that you use in a
    lab unless your teacher instructs you to do so.
 - Do not use any damaged or defective equipment.
 - Keep your lab area clean and free from clutter.
 - When you place something onto a lab bench, make sure that the
   object sits securely on the bench and will not fall or tip over.
 - Pay attention to where you are walking.
 - If you are working outside, be aware of your surroundings.
   Avoid poisonous plants and animals that live in the area.  Wear
   sunscreen and a hat that shades your neck and ears.
 - If an accident occurs, inform your teacher right away!

1.4 - What is Biology?
Biology is the study of life.

All living htings share seven properties:
1. Cellular Organization
    All living things are made up of one or more cells.  A cell is a
    highly organized, tiny structure that is enclosed in a thin covering
    called a membrane.
2. Homeostasis
    All living things must maintain a stable internal environment, in
    spite of changes in their external environment.
3. Metabolism 
    All living things must carry out chemical reactions in order to
    obtain and use energy.  All of the chemical reactions that occur
    in an organism make up its metabolism.
4. Responsiveness 
    All living things must be able to respond to their external
    environment.  This also implies that they must have some means
    of sensing their environment.
5. Reproduction 
    Most living things reproduce, thus creating more organisms of
    their own kind.  (A mule, which is the sterile offspring of a horse
    and a donkey, is a notable exception.)
6. Heredity
    All organisms that reproduce must be able to pass on their own
    traits to their offspring.  Evolution is the process in which
    inherited traits change over generations.
7. Growth
    All living things grow.  Some change as they grow, which is
    called development.
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