Which of the following statements about peptide bonds are true? 1) a tetrapeptide contains five amino acid residues. 2) peptide bonds form from nucleophilic attack by an electron pair on an alpha - amino nitrogen atom on an alpha - carboxyl carbon atom of another amino acid. 3) peptide bonds are ester linkages. 4) peptides are polymers of amino acids. 5) peptide bond formation is a hydrolysis reaction

The correct answers are:

2) Peptide bonds form from nucleophilic attack by an electron pair on an alpha - amino nitrogen atom on an alpha - carboxyl carbon atom of another amino acid and

4) Peptides are polymers of amino acids.

A peptide bond is an amide type of covalent chemical bond. It is formed between two amino acids:  C1 (carbon end) of one alpha-amino acid and N2 (nitrogen end) of another. Peptide bonds are the basis for the formation of a peptide chain and consequently protein.  Formation of peptide bond is a condensation process, meaning that when two amino acids combine and link, water molecule is released and dipeptide is a product of that reaction.

The statement that is true about peptide bonds is;

"Peptide bonds form from nucleophilic attack by an electron pair on an alpha-amino nitrogen atom on an alpha-carboxyl carbon atom of another amino acid."

Keywords; Proteins, amino acids, peptide bonds  

Level: High school  

Subject: Biology  

Topic: Macro-molecules  

Sub-topic: Peptide bonds and amino acids

explanation:

the universal gravitation equation. since the gravitational force is directly proportional to the mass of both interacting objects, more massive objects will attract each other with a greater gravitational force. if the mass of one of the objects is doubled, then the force of gravity between them is doubled.

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