Questions and Answers
Which classification of amino acids refers to the position of the nitrogen relative to the carbon chain?
Which of the following amino acids is the only achiral one among the standard amino acids?
What is the primary characteristic of the zwitterionic form of amino acids?
Which amino acid is represented by the abbreviation 'Met'?
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Which statement about the isomerism of amino acids is true?
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Which amino acid is a precursor for the transmission of nerve impulses?
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Which amino acid is known as a structural unit present in coenzyme A?
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Which of the following amino acids is commonly classified as a branched-chain amino acid?
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What does the L and D in Fischer's convention refer to regarding amino acids?
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At a pH of 7.4, which form of amino acids predominates?
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What is the net charge of amino acids at pH 7.4?
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Which aspect of amino acids is influenced by the R groups?
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What is the main reason cells synthesize L-isomers of amino acids?
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What is the general structure of common amino acids?
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What is the role of three-letter abbreviations and one-letter symbols in amino acids?
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How do uncommon amino acids differ from common amino acids?
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What type of carbon is present in amino acids due to its attachment to four different groups?
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Which of the following functions do amino acids NOT perform?
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What is the primary reason most amino acids are found in their L-form in biochemistry?
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What distinguishes L-amino acids from D-amino acids?
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Which of the following amino acids is known to play a role in detoxification?
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Which functional group is NOT typically found in the structure of amino acids?
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How many standard amino acids are commonly recognized based on their R groups?
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Which of the following is a characteristic of the zwitterionic form of amino acids?
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Study Notes
Function of Amino Acids
- Amino acids are essential for synthesizing proteins.
- Serve as precursors for nitrogen-containing compounds, including nucleic acid bases (purines and pyrimidines), porphyrins (heme, chlorophyll), folic acid, creatine, and glutathione.
- Act as chemical messengers and neurotransmitters.
- Involved in glucose synthesis and function as buffers.
- Participate in detoxification reactions, notably glycine, cysteine, and methionine.
Anatomy of Amino Acids
- Consist of an amino group (-NH2) and a carboxyl group (-COOH) attached to the same carbon (alpha-carbon).
- The alpha-carbon is a chiral center due to its four different substituents, allowing two unique spatial arrangements of amino acids (L and D isomers).
- L-amino acids are predominantly observed in biochemistry, denoting their structural configuration based on L-glyceraldehyde.
- Non-ionic forms are negligible in aqueous solutions; zwitterionic forms dominate at physiological pH (7.4).
- Charges of the zwitterionic form cancel out, making the net charge dependent on the side chain (R-group).
Classification of Amino Acids
- Amino acids are classified based on the carbon atom that bears the nitrogen: α, β, γ, etc.
- More than 700 amino acids exist, but 20 are crucial as the building blocks of proteins.
- These 20 amino acids are all α-amino acids, thus differing based on their R-groups.
Key Amino Acids
- Glycine (Gly or G): Simplest amino acid, achiral.
- Alanine (Ala or A).
- Valine (Val or V).
- Leucine (Leu or L).
- Isoleucine (Ile or I).
- Methionine (Met or M).
- Proline (Pro or P).
- Phenylalanine (Phe or F).
- Tryptophan (Trp or W).
- Asparagine (Asn or N).
- Glutamine (Gln or Q).
- Serine (Ser or S).
- Threonine (Thr or T).
Stereochemistry of Amino Acids
- Glycine is achiral; all other protein amino acids possess L-configuration at their α-carbon.
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Description
Explore the essential roles of alpha-amino acids in protein synthesis and their importance as precursors for various nitrogen-containing compounds. This quiz covers neurotransmitter functions and specific derivatives like glutathione and creatine. Test your knowledge on the biochemical significance of amino acids!