Polymers. Chemistry of Life.

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Lecture 24

• Polymers. Chemistry of Life.

Chapter 12.10 ? 12.17

• Monomers and Polymers
• Carbohydrates
• Photosynthesis
• Lipids and Proteins
• Next Exam

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Monomers and Polymers
Polymers are giant molecules that consist of
numerous (almost) identical subunits.
Polymers are held together by covalent bonds, not
by van der Waals forces as was thought earlier.
Natural polymers proteins, starch, cellulose,
rubber. Synthetic polymers polyethylene, nylon,
teflon.
Monomer is a any small molecule that can undergo
a reaction in which it is incorporated into a
large molecule containing many similar units.
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Examples of Polymers
Monomer vinyl chloride
Polymer polylinylchloride (PVC)
Ethene (C2H4)
polyethylene
Copolymers polymers that consist of 2 different
monomers. Elastomers polymers containing
monomers with two double bonds (chloroprene).
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Carbohydrates
Carbohydrates are carbon compounds with H and O
which contain 2 atoms of O for each atom of H.
They are produced from CO2 and H2O by green
plants in the process of photosynthesis using
solar energy.
Examples sugars (C6H12O6), starch,
cellulose. These examples are monosaccharides,
which may have either straight-chained or ring
structure. Two monosaccharide rings form a
disaccharide. Chains of more than 2
monosaccharides are called polysaccharide (e.g.,
cellulose).
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Photosynthesis

• 6CO2 6H2O energy ? C6H12O6 6O2
• This is photosynthesis, an endothermic reaction
  that goes with a catalyst, called chlorophyll.

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Lipids
Fats, oils, and similar substances are called
lipids.
Lipids contain only C, H, and O, and are formed
in plants and animals from carbohydrates. Lipids
consist of a glycerol molecule with 3 attached
fatty acid molecules.
Cholesterol is a lipid in the bloodstream,
deposits of which in arteries cause
atherosclerosis, a condition which restricts a
flow of blood.
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Proteins
Proteins are main elements of living cells. They
include C, H, O, N, S, and P.
Proteins are composed of 20 different amino acids.
The amino acids contain nitrogen.
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Nucleic Acids
Nucleic acids control the process of reproduction
of proteins and themselves.
Nucleic acid molecules consist of long chains of
nucleotides.
Each nucleotide has 3 parts, a phosphate group
(PO4), a pentose sugar, and a nitrogen
base. Ribonucleic acid (RNA) contains a sugar
called ribose (C5H10O5), Deoxyribonucleic acid (
DNA) contains deoxyribose (C5H10O4).
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The Human Genome
DNA controls the development and functioning of a
cell by determining the proteins the cell
makes. DNA also reproduces itself. Changes
occurring in the DNA structure due to errors of
reproduction, called mutations, lead to evolution.
Gene is a set of instructions for each protein in
the form of a certain sequence of
nucleotides. Genes make 3 of the human
genome. The purpose of the rest 97 is not known.
Origin of life experiments show that life might
have occurred spontaneously from simple
components.
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Summary
Life was developed from simple chemical compounds
with the help of single-celled organisms for a
very long time. DNA and RNA are the main agents
responsible for copying and reproduction of
living cells. The human genome represents all
genetic materials in a particular organism.
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Test 2
What is included
The types of fundamental interactions names,
scales, relative strength. Models of the atom
(Rutherford, Bohr). Quantum mechanics exclusion
principle, quantum numbers. Types of bonds in
molecules (ionic, covalent). Periodic law metals
and nonmetals, properties of elements, names of
the groups. Solutions, pH scale, essence of
chemical energy Combustion, fuels Types of
organic molecules
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Examples of questions

• The presence of a hydroxide group (OH) is a
  characteristic of
• an inorganic acid
• a base
• an alkane
• an aromatic hydrocarbon

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Examples of questions

• A chemical reaction that gives off energy is
  called
• endothermic
• combustion
• neutralization
• exothermic

Sodium is an example of an alkali metal a
halogen a noble (inert) gas an acid
The strongest of the fundamental interactions
is strong weak electromagnetic gravitational