Final answer:
Unfolded proteins are unique because they are prone to aggregation due to the loss of their functional native structure. This aggregation can disrupt cellular processes and is often irreversible, leading to a loss of function which may cause disease. Chaperones aid in proper protein folding to prevent these issues.
Step-by-step explanation:
What is unique about unfolded proteins is that they are prone to aggregation. This is because unfolded proteins lack the tight, precise structure that characterizes their functional native state. Instead of having a defined structure, which confers specific functions, unfolded proteins can begin to stick to each other, forming aggregates. These aggregates can be problematic as they potentially interfere with cellular processes and can cause diseases. As such, it is crucial for proteins to be correctly folded into their native structure, a task often aided by molecules known as chaperones.
Unfolded proteins are not highly stable; they are sensitive to further denaturation because they lack the secondary, tertiary, and if it exists, quaternary structures that provide stability. The primary structure, which is the linear sequence of amino acids, remains intact during denaturation, but without the higher-level structures, a protein's function is compromised. Although denaturation can sometimes be reversible, allowing the protein to return to its functional form, in some cases it is irreversible, leading to a permanent loss of function. An example of irreversible denaturation is cooking an egg; the egg white proteins coagulate and cannot return to their original, soluble state.