BIOLOGY
STRUCTURE OF PROTEINS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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It has a globular shape.
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It has iron in each heme group.
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It consists of more than one polypeptide chain.
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It has more than one peptide bonds.
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Detailed explanation-1: -Hemoglobin has a quaternary structure. It consists of two pairs of different proteins, designated the and chains. There are 141 and 146 amino acids in the and chains of hemoglobin, respectively. As in myoglobin, each subunit is linked covalently to a molecule of heme.
Detailed explanation-2: -The structure for hemoglobin is very similar to myoglobin except that it has a quaternary structure due to the presence of four protein chain subunits. Actually, there are two pairs of similar chains-two alpha types and two beta types. Each protein chain subunit contains a heme group with the iron attached.
Detailed explanation-3: -A hemoglobin molecule is made up of four polypeptide chains, two alpha chains of 141 amino acid residues each and two beta chains of 146 amino acid residues each.
Detailed explanation-4: -Quaternary structure exists in proteins consisting of two or more identical or different polypeptide chains (subunits). These proteins are called oligomers because they have two or more subunits. The quaternary structure describes the manner in which subunits are arranged in the native protein.
Detailed explanation-5: -It contains about 5000 individual atoms, excluding hydrogens, in 574 amino acid residues. The quaternary structure of hemoglobin consists of four peptide sub-units.