Biology Bio = life ology = the study of  Biology is the study of life.

 More specifically, it is the scientific study of life (i.e., life science).  Before we define life, let’s look at science.

The Nature of Science

 Scientific information is a changing body of knowledge.

 Many “facts” of the past are now known to be false. For example:  The Earth was flat  The sun revolved around the Earth.

 Disease was caused by evil spirits.

 Science is not a collection of eternal

truths.

 Some of what you learn this year will have to be changed one day.  Yet this does not mean that science has failed.  It means that science continues to succeed in advancing our understanding of the natural world.

 The goal of science is to understand the world around us.

 In the attempt to achieve that goal, scientists use the Scientific Method.

 The Scientific Method is a systematic approach to problem solving

The 6 steps of the Scientific Method 1. Observing, questioning, and/or

stating a problem

2. Forming a hypothesis - which is a possible explanation or an educated guess about some event in nature

The 6 steps of the Scientific Method 3. Testing the hypothesis : - develop a controlled experiment which contains both an experimental set up (which has only one experimental variable--- the thing being tested) and a control set up (which is identical to the experimental set up but does not contain the variable) With this type of set up any questions concerning the results of the experiment can be attributed to the one variable

4. Recording and analyzing data - Careful records of observations and information are kept. The data is usually presented in the form of

tables and graphs.

5. Forming a conclusion - This is based on the results of the experiment. If the experiment confirms the hypothesis, then the hypothesis gains credibility as to how nature works. If the results disagree with the hypothesis then either the experiment needs to be modified or a new hypothesis needs to be generated

6. Replicating the work - It must be possible for either the original experimenter or other researchers to duplicate, or reproduce, the experimental results.

 If a hypothesis is confirmed enough that it is unlikely to be disproved by future tests, it may become worthy of being called a theory. A theory is a time-tested concept that makes useful and dependable predictions about the natural world .

 To the true scientist, however, the scientific method is more a frame of mind that involves curiosity, creativity, and skepticism.  Skepticism is a refusal to accept an explanation without evidence or proof.  This “prove it” attitude encourages scientists to investigate phenomena and to develop new explanations and ideas

.

Universal Language: The Metric System

 So scientists can understand each other’s research, they use a universal system of measurement called the metric system.

 It is also known as the International System

of Units, or SI.

 It is used to measure length, volume, mass, and temperature.

 The metric system is a decimal system based on multiples of 10.

 Each unit is ten times larger or ten times smaller than the next unit.



PREFIXES

 centi = one hundredth (1/100)  milli = one thousandth (1/1000)  micro = one millionth (1/1,000,000)  nano =

one billionth (1/1,000,000,000)

 kilo = one thousand (1000)

Length The distance from one point

to another

meter (m) A meter (39.4 inches) is slightly longer than a yard.

1 meter = 100 centimeters (cm) 1 meter = 1000 millimeters (mm) 1 meter = 1,000,000 micrometers (um) 1 meter = 1,000,000,000 nanometers

(nm)

1000 meters = 1 kilometer (km)

Volume The amount of space an

object takes up.

Liquids Liter (L) A liter (1.06 quarts) is slightly more than a quart.

1 liter=1000 milliliters (

mL)

Solids (cc or cm 3 ) Cubic centimeter is the volume of a solid that measures 1 cm by 1 cm by 1cm.

1 milliliter is equal in volume to

1 cubic centimeter or 1mL = 1cc

Mass Gram (g) The amount of matter in an

object

A gram has a mass equal to about one paper clip.

1000 grams = 1 kilogram (kg) Weight is a measure of the pull of

gravity on mass.

In outer space, weight may vary with position but its mass always remains the

same.

Temperature The measure of

hotness or coldness

Degrees Celsius (°C) 0°C = freezing point

of water

100°C = boiling point

of water

 METRIC - ENGLISH EQUIVALENTS  2.54 centimeters (cm) = 1 inch (in.)  1 meter (m) = 39.4 inches (in.) or

1.09 yards

 1 kilometer (km) = 0.62 miles (mi)  1 liter (L) = 1.06 quarts (qt)

 METRIC - ENGLISH EQUIVALENTS  250 milliliters (mL) = 1 cup  1 kilogram (kg) = 2.2 pounds (lb)  28.3 grams (g) = 1 ounce (oz)  °C = 5/9 x (°F-32)