What is the function of the protein $GLUT-4$?

Zwitterions are ionized species of

$A$ quaternary protein consisting of two $\alpha$-chains and two $\beta$-chains is:

Select the correct match for $X$ and $Y$:

Column $X$	Column $Y$
$(1)$ Primary protein	$(P)$ Globular or fibrous form
$(2)$ Secondary protein	$(Q)$ Three-dimensional arrangement of a single polypeptide chain
$(3)$ Tertiary protein	$(R)$ Gene-controlled
$(4)$ Quaternary protein	$(S)$ Helical or pleated sheet form

$A$ nanopeptide contains .... peptide linkages.

The triple helical structure of collagen was published in Nature in $1954$, and the analysis of the allowed conformations of proteins was performed through the use of the: