The secondary structure of a protein refers to

The structure of protein that is unaffected by heating is ... .

Protein found in a biological system with a unique three-dimensional structure and biological activity is called a native protein. When a protein in its native form is subjected to a physical change like a change in temperature or a chemical change like a change in $pH$,denaturation of proteins takes place. Explain the cause.

$A$ codon has a sequence of $\underline{A}$,and specifies a particular $\underline{B}$ that is to be incorporated into a $\underline{C}$. What are $\underline{A}, \underline{B}, \underline{C}$?
$\underline{A} \quad \underline{B} \quad \underline{C}$

Which of the following statements is $NOT$ correct for amino acids?

Determine the configuration of the given compound.