Chapter 1 - The Science of Biology

1-1 What is Science?

The Goal of Science
1) deals only with the natural world
2) to collect and organize information
3) propose explanations that can be tested

Science - using evidence to learn about the natural world; a body of knowledge

Science begins with observations

data - the information gathered from observations
quantitative data = numbers
qualitative data = descriptive

inference - a logical interpretation based on prior knowledge or experience

hypothesis - a proposed scientific explanation

***Science is and ongoing process***

1-2 How Scientist Work (page 8)

Spontaneous generation - the idea that life could arise from non-living matter

Francesco Redi (1668) (Fig 1-8)
Lazzaro Spallanzini (Fig 1-10)
Louis Pasteur (1800's) (figure 1-11)


Scientific Method:

1) Ask questions, make observations
2) Gather information
3) Form a hypothesis
4) Set up a controlled experiment

Manipulated variable - the variable that is deliberately changed (independent variable)
Responding variable is variable that is observed ( aka dependent variable)

5)Record and analyze results
6)Draw a conclusion

***Field studies, models ***

Theory - a well-tested explanation that unifies a broad range of observations. NOT ABSOLUTE

1-3 Studying Life (page 16)

biology means the study of life / Bios = life -logy = study of

frogThe 8 Characteristics of Living Things:

1) Cell - smallest unit of life
unicellular = single celled
multicellular = many celled

2) Reproduction
sexual reproduction -DNA from two different parents
asexual reproduction - single parent (cloning, budding)

3) Genetic Code - directions for inheritance (DNA)

4) Growth and Development
growth = getting larger

development = changing shape and structure

Differentiation = cells that look different and perform different functions

5) Obtain and use energy
metabolism - chemical reactions

plants - photosynthesis Animals - eating

6) Response to the Environment
stimulus - a signal to which we respond
response - a reaction to a stimulus

Ex: school bell rings, we move to next class

7) Internal Balance
homeostasis -internal conditions
remain constant

Ex: lizards sun themselves
8) Evolution - Change over time

Branches of Biology:

Zoologists - animals Botanist - plants
Paleontologist - ancient life Cytologist - cells

Levels of organization (page 21, figure 1-21)

Molecules >Cells > Tissues > Organs > Organ systems > Organisms > Population > Community > Ecosystem > Biosphere

1-4 Tools and Procedures

Common Measurement System



Metric system - decimal system of measurements, units are scaled on multiples of 10

Length Meter, Centimeter, Kilometer Ruler, Meter Stick
Volume Liter, Milliliter Graduated Cylinder
Mass Kilogram, Gram Balance, scale

Temperature - The measure of hotness (Celsius)

Analyzing data -- Tables, Graphs, Charts, Drawings, Models, etc.

Microscopes - produce a magnified image of structures

Light Microscope
May be Simple or Compound
(one lens) or (two or more lenses)

**Specimen can remain alive**

Electron Microscope
SEM - 3-D image
TEM - through an image

**Specimens cannot be observed while alive**

Laboratory Techniques
Cell culture - group of cells grown in a nutrient solution from a single original cell

Cell fractionation - technique in which cells are broken into pieces and parts are separated