Question

The specific spatial arrangement of amino acid residues that are close to each other in the polypeptide chain is called______the structure of a protein.
a. primary.
b. secondary.
c. tertiary.
d. quaternary .

Answer 1

Answer:

c. tertiary.

Explanation:

In this case, we can review the definition of each level of structuration in the proteins:

Primary structure

In the primary structure, the amino acids are linked by peptide bonds. That is, the order of the amino acids is the criterion that defines this type of structure.

Secondary structure

In the secondary structure, we have to look at the way in which the protein is folded. The options are:

  -) Beta-laminar: A structure in which the protein has a planar shape.

  -) Alpha-helix: A structure in which the protein has a cross-strand form.

Tertiary structure

In the tertiary structure, the R groups that the amino acids have in the primary structure can generate interactions with each other. Interactions such as hydrogen bridges, dipole-dipole, hydrophobic interactions. This makes the protein have a very specific three-dimensional structure, on which its function depends.

Quaternary structure

In the quaternary structure, several subunits may be attached, or there may be prostatic groups (metals that can help to attach various protein units).

With all these in mind, the deffinition that fits with the description in the question is the tertiary structure.

I hope it helps!