The simplest amino acid is

$A$: Tertiary structure of protein molecules makes them biologically active.
$R$: It is the native configuration of protein molecules maintained by multiple covalent bonds only.

Briefly describe the types of groups participating in the structure of amino acids.

Can you describe what happens when milk is converted into curd or yoghurt from your understanding of proteins?

Aleurone grains are

Proteins mainly contain: