Concept explainers
Interpretation:
The reason for the fact that amino acids are
Concept introduction:
A protein is the polymerized form of amino acids that are linked together by peptide bonds. A small chain of polymerized amino acids form a peptide chain. Several peptide chains are linked together to form a protein. Thus, the molecular weight of a protein is more than that of the peptide chains.
A crosslink is the connection between two chains or molecules of a particular structure. For example, two peptide chains may be cross-linked with each other to form a complete protein.
A covalent bond is the type of bond in which the electron pair is shared between the two atoms.
Want to see the full answer?
Check out a sample textbook solutionChapter 3 Solutions
Biochemistry
- REFLECT AND APPLY A sample of an unknown peptide was divided into two aliquots. One aliquot was treated with trypsin; the other was treated with cyanogen bromide. Given the following sequences (N-terminal to C-terminal) of the resulting fragments, deduce the sequence of the original peptide. Trypsin treatment AsnThrTrpMetIleLysGlyTyrMetGlnPheValLeuGlyMetSerArg Cyanogen bromide treatment GlnPheValLeuGlyMetIleLysGlyTyrMetSerArgAsnThrTrpMetarrow_forwardREFLECT AND APPLY You are studying with a friend who says that the hydrogen-bonded portions of tRNA play no important role in its function. What is your reply?arrow_forwardRECALL Give the name of the base, the ribonucleoside or deoxyribonucleoside, and the ribonucleoside triphosphate for A, G, C, T, and U.arrow_forward
- REFLECT AND APPLY The structures of tRNAs contain several unusual bases in addition to the typical four. Suggest a function for the unusual bases.arrow_forwardREFLECT AND APPLY A sample of a peptide of unknown sequence was treated with trypsin; another sample of the same peptide was treated with chymotrypsin. The sequences (N-terminal to C-terminal) of the smaller peptides produced by trypsin digestion were as follows: MetValSerThrLysValIleTrpThrLeuMetIleLeuPheAsnGluSeArg The sequences of the smaller peptides produced by chymotrypsin digestion were as follows: AsnGluSerArgValIleTrpThrLeuMetIleMetValSerThrLysLeuPhe Deduce the sequence of the original peptide.arrow_forwardREFLECT AND APPLY Many properties of acetic acid can be rationalized in terms of a hydrogen-bonded dimer. Propose a structure for such a dimer.arrow_forward
- REFLECT AND APPLY In the early days of molecular biology, some researchers speculated that RNA, but not DNA, might have a branched rather than linear covalent structure. Why might this speculation have come about?arrow_forwardRECALL Is it possible to form cyclic peptides without bonds between side chains of the component amino acids?arrow_forwardREFLECT AND APPLY Starting with a Fischer projection of D-fructose, write equations showing the formation of -D-fructopyranose, -D-fructofuranose, -D-fructopyranose, and -D-fructofuranose.arrow_forward
- REFLECT AND APPLY Why do amino acids other than methionine occur in the N-terminal position of proteins from eukaryotes?arrow_forwardREFLECT AND APPLY Common proteins are polymers of 20 different amino acids. How big a protein (how many amino acid residues) would be necessary to have an Avogadros number of possible sequences?arrow_forwardREFLECT AND APPLY Would you expect tRNA or mRNA to be more extensively hydrogen bonded? Why?arrow_forward
- BiochemistryBiochemistryISBN:9781305961135Author:Mary K. Campbell, Shawn O. Farrell, Owen M. McDougalPublisher:Cengage Learning