Polymers are formed by connecting monomers with covalent bonds through
loss of a water molecule.
This is called a dehydration, or condensation, reaction.
Polymers are disassembled to monomers by hydrolysis.
Covalent bonds are broken by the addition of water molecules.
Making and Breaking Polymers:
Aldoses and ketoses are structural isomers.
Glucose and galactose each has an asymmetric carbon and are
Cellulose is a major component of the tough cell walls in plants, and
is difficult to digest.
Animals stockpile glycogen in granules within organelles called
mitochondria in liver and muscle cells.
The polymer is a strong but flexible structural polysaccharide of
insect exoskeletons and can also make biodegradable surgical threads.
The fatty acid tails are nonpolar hydrocarbon chains that are
Such lipids may also be called triglycerides.
The straight geometry of saturated fat allow them to pack tightly and they are usually solids
at room temperature.
Most animal fats are saturated.
The mostly cis double bonds cause the molecule to bend.
Unsaturated fats pack loosely and are usually liquid (oils) at room
However, trans double bonds can cause a Lipids to behave like a
Cis unsaturated fats have large components on the same side.
Most proteins fold into a specific 3-dimensional shape (conformation)
with four levels of structure.
Each amino acid has a different side chain (R group).
Peptide bonds formed by dehydration reactions link the carboxyl group
of one amino acid to the amino group of the next.
The polypeptide has a repetitive backbone to which the side chains are
Present in our sweat, tears, and saliva, lysozyme is an enzyme that
prevents infection by destroying molecules in bacteria cell walls.
The groove in the protein recognizes and binds to target molecules on
To be active, the enzyme must be in a specific 3-dimensional shape, or
The carbon atoms on the sugar are given prime numbers: 1' through 5'.
The nitrogenous base is either a pyrimidine - Cytosine (C), Thymine
(T), and Uracil (U) - or a purine - Adenine (A) and Guanine (G).
Thymine is found in DNA (Deoxyribonucleic Acid), while Uracil is found
in RNA (Ribonucleic Acid).
The phosphate group is attached to the 5' carbon, forming a
A DNA molecule is usually double-stranded, with the sugar-phosphate
backbone of two polynucleotide strands on the outside of the helix.
Holding the two strands together are pairs of nitrogenous bases
attached to each other by hydrogen bonds.
Adenine (A) can pair only with Thymine (T).
Guanine (G) can pair only with Cytosine (C).