Introduction chapters1and2

Chapter 1:
A. Science is:
1. Investigating and understanding the
natural world
2. Explaining events in the natural world
3. Using explanations to make
4. Making observations, collecting data,
inferring, hypothesizing processing,
questioning, testing, evaluating,
recommending . . .
B. How Scientists Work
Experiments on Generation of Life:
1. Redi tested his hypothesis testing one
variable against a control group and
discovered that maggots were not
produced from rotting meat but from
2. Spallanzani proved Redi’s results and
disproved Needham’s support of
spontaneous generation
Experiments (cont)
3. Pasteur improved on results
further by using a curved-neck
flask thus finally proving that living
things come from living things
C. Studying Life
1. Characteristics of Living Things
Made up of cells
Universal genetic code
Grow and develop
Use materials and energy
Respond to the environment
Maintain a stable internal environment
As a group, change over time
2. Branches of Biology
a. molecular biology
b. cellular biology
c. histology, physiology, anatomy
d. zoology, bacteriology, botany
e. ecology, environmental science
And more . . .
D. Tools and Procedures
1. Common Measurement: Most
scientists use a revised metric
system known as: SI or
International System of Units
2. Computers to collect and store
3. Microscopes: Light and electron
4. Cell Cultures: reproduction of
5. Cell fractionation: separation of
cell parts
6. Safety – see appendix B and
wash hands after labs!
Chapter 2: Chemistry of Life
A. Matter
1. Atoms, electrons, protons, and
2. Elements/isotopes
3. Chemical compounds held together
by ionic or covalent bonds
B. Water
1. Polar compound
2. Because of polarity, hydrogen bonding
occurs leading to adhesion and
3. Can be used to make mixtures such as
solutions and suspensions
4. Neutral (7) on the pH scale
a) Acids (below 7) have higher
concentration of H+ ions
b) Bases (7>14) have lower H+
concentration than water.
C. Carbon Compounds
1. What’s special about carbon?
a) Has 4 valence electrons and can
bond with various elements
b) Can bond with other carbons
forming long chains and rings,
more complex and larger
2. Macromolecules: 4 groups of large polymers
found in living things (organic molecules)
a) Carbohydrates
i. contain C, H, and O in a ratio of 1:2:1
ii. are major sources of energy
iii. Examples are sugar,starch,
monosaccharides and polysaccharides
b) Lipids
Made of mostly C and H
Store energy
iii. Not soluble in water
iv. Examples are fats, oils and waxes
c) Nucleic Acids: RNA and DNA
Units called nucleotides contain H, O,
C, N and P
ii. Store and transmit genetic information
d) Proteins
i. Polymers made of amino acids
containing H, O, C, and N
ii. Control rates of reaction, regulate cell
processes, form bones and muscles,
transport substances in and out of
cells, fight disease
IV. Chemical Reactions and Enzymes
A. Chemical Reactions
1. New substances are formed through
the breaking of bonds in reactants to
form new bonds in products
2. Exothermic: give off energy and often
occur spontaneously
3. Endothermic: require a source of
4. Examples:
CO2 + H2O ↔C6H12O6 + O2
H2 + O2 →H2O
B. Reaction Rates
1. Catalysts are chemicals that speed up a
chemical reaction by lowering activation
2. Enzymes: proteins speed up chemical
reactions occurring in cells
3. Enzymes provide a site for reactants
(substrates) to come together