Amino Acids

Overview

Amino acids are organic compounds that serve as the building blocks of proteins, characterized by the presence of both an amino group (–NH₂) and a carboxyl group (–COOH) in their structure. They can be classified into essential and non-essential amino acids, with essential amino acids needing to be obtained through diet as the body cannot synthesize them. Amino acids exist primarily in a dipolar ionic form known as zwitterions, which allows them to exhibit both acidic and basic properties. They can link together through peptide bonds to form peptides and proteins, playing crucial roles in various biological processes, including enzyme function, hormone regulation, and cellular structure

Questions and Answers

  1. What are amino acids?

    Amino acids are organic compounds that contain both an amino group (–NH₂) and a carboxyl group (–COOH), serving as the fundamental building blocks of proteins.

  2. How are amino acids classified?

    Amino acids are classified into two main categories: essential amino acids, which must be obtained from the diet, and non-essential amino acids, which the body can synthesize.

  3. What is the significance of zwitterions in amino acids?

    Zwitterions are dipolar ions that have both positive and negative charges within the same molecule, allowing amino acids to exhibit both acidic and basic properties, which is crucial for their function in biological systems.

  4. How do amino acids link together to form proteins?

    Amino acids link together through peptide bonds, which are formed by a condensation reaction between the carboxyl group of one amino acid and the amino group of another, releasing a molecule of water.

  5. What are the two types of amino acids based on their side chains?

    Amino acids can be classified as polar (hydrophilic) or non-polar (hydrophobic) based on the nature of their side chains (R groups), influencing their interactions and functions in proteins.

Multiple-Choice Questions

  1. Which of the following is an essential amino acid?

    a) Glycine
    b) Alanine
    c) Leucine
    d) Serine
    Answer: c) Leucine

  2. What type of bond forms between amino acids during protein synthesis?

    a) Hydrogen bond
    b) Ionic bond
    c) Peptide bond
    d) Covalent bond
    Answer: c) Peptide bond

  3. Which amino acid is known for having a sulfur atom in its side chain?

    a) Methionine
    b) Valine
    c) Glutamic acid
    d) Lysine
    Answer: a) Methionine

  4. What is the term for amino acids that can be synthesized by the human body?

    a) Essential amino acids
    b) Non-essential amino acids
    c) Conditional amino acids
    d) Branched-chain amino acids
    Answer: b) Non-essential amino acids

  5. Which of the following amino acids is classified as acidic?

    a) Lysine
    b) Glutamic acid
    c) Alanine
    d) Phenylalanine
    Answer: b) Glutamic acid