Download Chapter 3 The Chemical Building Blocks of Life

Chapter 3
The Chemical
Building Blocks of Life
Trevor Morera, Daniel
Guevarra, Fabian Abarca
Carbohydrates
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Monosaccharides – single sugar that is simple,
containing as few as three carbon atoms, but
when they play a central role in energy storage,
they contain six carbons
C6H12O6 is not only the chemical formula for
glucose, but for both structural isomers and
stereoisomers
Disaccharides (two linked monosaccharides) are
effective reservoirs of glucose and serve as
transport molecules and provide nutrition in plants
and animals, respectively.
Carbohydrates (2)
 Polysaccharides
which are longer
polymers made of monosaccharides
joined through dehydration reactions
 Starch is a storage polysaccharide,
consisted of alpha glucose molecules
linked in long chains, similarly to cellulose
(but with beta glucose)
 Chitin, found in shellfish and fungi, is a
substituted version of glucose.
Lipids
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Lipids are hydrophobic molecules (insoluble in
water).
Storage fats are all one kind of lipid. Oils, waxes, and
some vitamins are also lipids
Fats are complex polymers of fatty acids attached to
glycerol
A fat molecule is a triglyceride, containing three fatty
acids.
Saturated fats have all carbon atoms in the fatty
acid chains bonded to at least two hydrogen atoms,
having all the hydrogen atoms possible
Unsaturated fats have fatty acids with double
bounds between pairs of successive carbon atoms.
Lipids (2)
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Monounsaturated fats have one double bond.
Polyunsaturated fats have more than one double
bond.
Fats are excellent energy-storage molecules
Most fats contain over 40 carbon atoms, ratio of
energy storing bonds in fats is more than twice
that of carbohydrates
Phospholipids are complex lipids that form the
core of all biological membranes, the basic
structure of a phospholipid is of three subunits:
glycerol, fatty acids, and a phosphate group
Nucleic Acids
 Nucleic
acids are information molecules.
 Two main varieties of nucleic acids are
DNA and RNA.
 DNA encodes genetic information use to
assemble proteins.
 Nucleic acids can serve as templates to
make precise copies of themselves.
Nucleic Acids (2)
 Nucleic
acids are long polymers of
nucleotides.
 A nucleic acid is basically a chain of fivecarbon sugars
 RNA is a transcript of a DNA strand
 Adenine, a nucleotide, is a key part of
ATP, other nucleotides are important in
NAD+ and FAD
Proteins
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Proteins are molecules with diverse structures and functions,
composed of polymers of amino acids (an amino group
and an acidic carboxyl group)
Protein functions are categorized into the following:
enzyme catalysis, defense, transport, support, motion,
regulation, and storage
There are 20 different amino acids, with a generalized
structure of amino and carboxyl groups bonded to a
central carbon atom, with an additional hydrogen and
functional side R group
Peptide bonds link amino acids
Levels of structure are: primary (amino acid sequence),
secondary (hydrogen bonding patterns), tertiary (folds and
link), and quaternary (subunit arrangements)
Proteins (2)
 Motifs
are made from secondary structure
elements that combine, fold, or crease
 Domains are distinct parts of a protein
that make it up
 Protein folding relies on chaperone
proteins
 Improper folding results to diseases
 Denaturation causes proteins to become
inactive