| 1.
A polypeptide is
a linear polymer of amino acids, linked together by peptide
bonds. |
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| 2. Proteins are
functional entities composed primarily of polypeptides
and often non-polypeptide cofactors. A protein without
its co-factors is known as an apoprotein. |
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| 3.
All terrestrial organisms use the same set of 19 L-form
amino acids and 1 imino
acid, proline. |
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| 4. Translation is
the process by which polypeptides are synthesized based
on information carried in an mRNA sequence,
a tRNA adaptor.
This reaction is catalyzed by the ribosome. |
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| 5.
All terrestrial organisms, with a few minor exceptions,
use exactly the same the genetic
code to specify polypeptide sequences
synthesized by the process of translation. The exceptions
primarily involved the use of stop codons to encode amino
acids and the reassignment of a few codons to different
amino acids. |
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| 6.The
ubiquity of the genetic code indicates that it was a
trait present in the last common ancestor of all organisms. |
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| 7.
The presence of minor variations in the genetic code
suggests that it is not a predetermined, obligate feature
of the translation process, but an inherited trait. |
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| 8. Amino
acids are linked together in a condensation
reaction that leads to the formation of a peptide
bond. |
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| 9.
During translation, new amino acids are added to the –COOH
(C) terminus of the growing polypeptide chain. |
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| 10.
A functional protein can consist of one or more polypeptides. |
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| 11.
A specific polypeptide can be part of more than one protein. |
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| 12.
Amino acids are distinguished by the "R" groups,
which attach to the alpha C. These R groups of different
sizes: some are hydrophobic, hydrophilic, positive or
negatively charged at physiological pH. |
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