Question

of the following macromolecules, which one(s) would be considered extensible?

Explanation:

Answer:

To determine extensible macromolecules, we analyze each structure:

1. First structure (sodium alkyl sulfate): A detergent (lipid - like, single - chain), not a polymer with extensible (polymeric, chain - extending) properties.
2. Second structure (phenylalanine, an amino acid): A monomer (building block of proteins). Proteins are polymers of amino acids, and the protein polymer (formed by linking amino acids) is extensible (can have long chains, be stretched/extended).
3. Third structure (disaccharide, e.g., maltose): A carbohydrate dimer. Polysaccharides (polymers of sugars) can be extensible (e.g., cellulose, starch chains), but this is a dimer (not a polymer with extensive chain - like extensibility in the same way as protein or nucleic acid polymers here).
4. Fourth structure (nucleotide triphosphate, e.g., ATP - like, but also a nucleic acid monomer): Nucleic acids (polymers of nucleotides) are extensible (long chains of nucleotides).

Wait, correction: The second structure is an amino acid (monomer of protein), and proteins (polymers) are extensible. The fourth is a nucleotide (monomer of nucleic acids, like DNA/RNA), and nucleic acid polymers are extensible. The third is a disaccharide (not a polymer with the same extensible polymer structure as protein/nucleic acid). The first is a lipid - like detergent (not a polymer for extensibility).

So the extensible ones are the amino acid (second structure, monomer of protein, and the protein polymer is extensible) and the nucleotide (fourth structure, monomer of nucleic acid, and nucleic acid polymer is extensible)? Wait, no—wait, the question is about macromolecules (polymers) or their monomers? Wait, "macromolecules" are polymers. Wait, maybe I misread: the first is a lipid (not a polymer macromolecule), second is an amino acid (monomer, not macromolecule), third is a disaccharide (oligomer, not macromolecule), fourth is a nucleotide (monomer, not macromolecule). Wait, no—maybe the question has a typo, or I misinterpret. Wait, extensible macromolecules are those with long, flexible chains (like proteins, nucleic acids, some polysaccharides). Wait, the second structure is an amino acid (monomer of protein, which is a macromolecule). The fourth is a nucleotide (monomer of nucleic acid, a macromolecule). But the question is "of the following macromolecules"—but these are monomers. Wait, maybe the diagrams are misrepresented. Wait, maybe the second is a protein (no, it's an amino acid), fourth is a nucleic acid (no, it's a nucleotide). Wait, perhaps the intended answer is the second (amino acid, part of protein macromolecule which is extensible) and fourth (nucleotide, part of nucleic acid macromolecule which is extensible), or maybe the third (disaccharide is part of polysaccharide, but disaccharide is not a macromolecule). Wait, I think the correct approach: Extensible macromolecules are polymers with long chains that can be stretched, like proteins (polymers of amino acids) and nucleic acids (polymers of nucleotides). The monomers (amino acid, nucleotide) are not macromolecules, but if the question considers the monomer as part of the macromolecule's building block (and the macromolecule is extensible), then the second (amino acid, for protein) and fourth (nucleotide, for nucleic acid) are the ones whose macromolecules (protein, nucleic acid) are extensible. The first is a lipid (not a polymer macromolecule), third is a disaccharide (oligomer, not a macromolecule polymer with extensibility like protein/nucleic acid).

So the answer is the second (phenylalanine, amino acid, part of protein macromolecule) and fourth (nucleotide, part of nucleic acid macromolecule). But since the options are the diagrams:

• Second structure (amino acid): Its macromolecule (protein) is extensible.
• Fourth structure (nucleotide): Its macromolecule (nucleic acid) is extensible.

But maybe the question has a mistake, but based on macromolecule types: Proteins (amino acid polymers) and nucleic acids (nucleotide polymers) are extensible. So the second (amino acid monomer, leading to protein) and fourth (nucleotide monomer, leading to nucleic acid) are the ones whose macromolecules are extensible. So the answer is the second and fourth options (the amino acid and the nucleotide - like structure).