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)

experiment

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
7)Repeat

***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

measuring

 

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

UNIT TOOL
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