Q17 of 50 Page 1

Explain what is meant by the following:

(i) Peptide linkage


(ii) Pyranose structure of glucose


(i) The amide linkage between two α-amino acids formed with the loss of a water molecule is called a peptide linkage.


Peptide linkage is the peptide bond () formed between amino acids. It is a covalent bond formed between amino group of one molecule and carboxylic acid group of another molecule, causing the release of one molecule of water.



(ii) The name pyranose comes from pyran chemical structure that includes a six-membered ring consisting of five carbon atoms and one oxygen atom and containing two double bonds.



Structure of pyran.


The pyranose structure of glucose includes a six membered ring with 5-carbon atoms and one oxygen atom having no double bonds.



Pyranose structure of glucose.


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(ii)


OR


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