BIOLOGY
AMINO ACIDS
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Serine and Alanine
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Alanine and Valine
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Serine and Threonine
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Valine and Isoleucine
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Detailed explanation-1: -Two amino acids, serine and threonine, contain aliphatic hydroxyl groups (that is, an oxygen atom bonded to a hydrogen atom, represented as ―OH). Tyrosine possesses a hydroxyl group in the aromatic ring, making it a phenol derivative.
Detailed explanation-2: -Six amino acids have side chains that are polar but not charged. These are serine (Ser), threonine (Thr), cysteine (Cys), asparagine (Asn), glutamine (Gln), and tyrosine (Tyr).
Detailed explanation-3: -Serine is one of two hydroxyl amino acids. Both are commonly considered to by hydrophilic due to the hydrogen bonding capacity of the hydroxyl group.
Detailed explanation-4: -Threonine is an other hydroxyl-containing amino acid. It differs from serine by having a methyl substituent in place of one of the hydrogens on the carbon and it differs from valine by replacement of a methyl substituent with a hydroxyl group. Note that both the and carbons of threonine are optically active.
Detailed explanation-5: -There are six amino acids under this. Serine and threonine have hydroxylic R side chains of different sizes. Asparagine and glutamine have amide-bearing side chains of different sizes. Tyrosine has a phenolic group and is aromatic.