Download Biochemistry: Monomers and Polymers

Biochemistry: Monomers and
Polymers
Carbohydrates, lipids, proteins, and
nucleic acids
Monomers
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Glucose
Amino acids
Nucleotides
Fatty acids
Polymers
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Carbohydrates
Nucleic acids
Lipids
Proteins
Carbohydrates
• The word carbohydrate literally means
“watered carbon.”
• Do you remember the chemical formula for
glucose? How does that remind us of the
formula for water?
• C6H12O6
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Carbohydrate Definition
• Carbohydrates are molecules composed of carbon,
hydrogen, and oxygen – they are polymers of
glucose.
– They are polysaccharides.
• Carbohydrates can be broken down to provide a
source of usable chemical energy for cells.
• They are a major part of plant cell structure (our
producers).
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Carbohydrates: Cellulose, Starch, and
Glycogen
• Cellulose is a rigid, straight polysaccharide, which
makes up the cell walls of plants.
– it is tough and fibrous (a good source of your fiber).
• Starch is a polysaccharide made and stored by plants.
– It is broken down for energy by both plants and animals.
• Glycogen is a highly branched polysaccharide of
glucose
– It serves as a form of energy storage in animals and fungi.
– The polysaccharide structure represents the main storage
form of glucose in the body.
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Lipids
• Lipids are nonpolar, uncharged, molecules
that include fats, oils, and cholesterol.
– Fats and oils are made up of fatty acids
bonded together.
– Fatty acids are the monomers for lipids.
– Fatty acids are made up of carbon chains
bonded with oxygen and hydrogen.
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Lipid Functions
• Lipids have several different functions. They are:
– broken down as a source of energy (triglycerides).
– make up cell membranes (phospholipids)
– used to make hormones (see structure below).
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Fats and Oils Are Made Up of
Triglycerides
Glycerol
Fatty acid tails
Triglycerides
are made when
three fatty
acids are
attached to a
glycerol
molecule.
Fats and oils are made up of fatty acids bound together as
triglycerides. The fatty acids can be either saturated or
unsaturated (see next slide).
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Fatty Acids: Saturated and
Unsaturated
• A saturated fatty acid has no C-C bonds.
Unsaturated does.
• Olive oil is high in unsaturated fat while butter is
very high in saturated fat.
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The more the
oil is
unsaturated
(has more
carboncarbon
double
bonds) the
lower its
melting
temperature.
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Lipids make cell membrane
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Proteins
• Proteins are polymers of amino acid
monomers – the polymers are created in the
cell as part of DNA translation process.
• Twenty different amino acids are used to build
proteins in organisms.
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Def. of Amino Acid
• Amino acids are molecules that contain C, H,
O, N, and sometimes sulfur.
– Our bodies are able to make 12 of the 20 amino acids, the
rest come from what you eat.
– The amino acid monomers are linked together by peptide
bonds to form protein polymers.
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Amino acids give proteins shape
• Proteins differ in the number and order of amino acids.
• Amino acids interact to give a protein its shape, which
determines its biological function(s).
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Nucleic Acids
• Nucleic acids are polymers of monomers
called nucleotides.
• Nucleotide – is composed of a sugar, a
phosphate group, and a nitrogen containing
molecule called a base (we will talk a lot more
2nd semester about these).
• DNA and RNA are the two types of nucleic
acids.
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Example: Nucleotide Monomer
A phosphate group
nitrogen-containing molecule,
called a base
deoxyribose (sugar)
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Nucleic Acids - Polymers
This shows the two strands
of DNA that connect, via
hydrogen bonds, and twist to
form a double helix. RNA is
single stranded.
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Nucleic Acids
• DNA stores genetic information.
DNA
• RNA builds proteins.
RNA
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Entrance Ticket
• Name the monomers for these polymers:
– Protein
– Carbohydrate
– Nucleic acid
– Lipid
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