Download Basic biochemistry

Outline for Chemistry of Life
Biology 520
Main class page | Homework
I. Atoms


overview of biological chemistry
and, one more overview, this one focusing more on macromolecules (see
below)
A. protons, neutrons, and electrons – p. 34, fig. 2-1
B. CHNOPS
C. isotopes - fig 2-3 p. 36
II. Molecules
A. 2 or more atoms
B. bonds give each atom 8 outer electrons
III. Bonds
A. covalent - sharing electrons - see p. 37, fig 2-4
1. usually elements from the right side of the table
2. examples – note number of covalent bonds formed by C, N, O,
and H
3. polar vs. non-polar - fig. 2-6 p. 40
B. Ionic - transfer of electrons
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Example – salts such as NaCl - ions
In living things the ions dissolve and exist as separate ions
(these ions are sometimes called electrolytes)
fig. 2-4 p. 37
C. Hydrogen bonds - fig. 2-7, p. 41- a weak bond between:
1. H covalently bonded to an electronegative atom, such as O, N,
or Cl;
2. an atom with non-bonded electrons
3. example - water molecules are attracted to each other because of
hydrogen bonding; the halves of DNA are also held together by
this type of bond
D. characteristics of water (result from hydrogen bonds and shape of the
molecule) - p. 40-43


more on water properties
another animation
1. high boiling point
2. ice floats
3. conducts electricity
4. many items dissolve or form suspensions in water – fig. 2-9
5. cohesion and surface tension – fig. 2-8
6. high specific heat (absorbs a lot of energy to heat up).
IV. Acids and bases - p. 43, fig. 2-10
A. definitions and pH scale
B. buffers
C. importance of acid/base in biology: blood, stomach, etc.
V. Organic (bio)molecules
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organic molecules are molecules found in/made by living things - see fig.
2-12
overview of biological molecules and percentages of each type
molecule of the month - organic molecule illustrations by D. Goodsell
A. polymers in general
1. definitions and descriptions
2. most biomolecules are polymers – p. 46 fig. 2-13
B. carbohydrates (p. 45-46)
1. monomer = sugar (there are several kinds). General formula is
CnH2nOn - fig 2-14
2. examples of carbohydrates:
a. starch
b. glycogen
c. cellulose
d. chitin
C. proteins (p. 48-49)
1. monomer = amino acid - fig. 217


3-D amino acids
animated amino acid
2. polymer = protein with
complex 3-D structure - example
fig. 2-18
3. levels of structure
4. examples
D. nucleic acids (p. 48)
1. monomer = nucleotide (fig. 2-16)
2. examples - DNA and RNA
E. Lipids (p. 47)

microscope images
1. monomer = not always the same (note examples below)
2. fatty acids - glycerol with long hydrocarbon tail (used for energy
storage) - fig. 2-15 - link to glycerol to create a fat molecule
3. phospholipids - similar to fatty acids with a charged end; found
in membranes.
4. other examples include cholesterol and steroid hormones
VI. Enzymes and chemical reactions (p. 50-53)
A. enzymes are proteins, so they are made of amino acids and have
complex three-dimensional structure
B. enzymes are biological catalysts. They lower the "activation
energy" needed to start a reaction, so they make the reactions go
faster. Enzymes control every chemical reaction that takes place
inside living things.

how do they do this? See fig. 2-20 and 2-22
C. enzymes are specific for particular reactions. Each step in a
reaction process has its own enzyme. For example, getting the
energy out of sugar (respiration) requires more than 20 separate
enzymes - see fig 2-23
D. Enzymes can be sped up or slowed down by changing
conditions such as temperature, pH, and concentration of reactants
and products.
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