Denaturing
Next, I will do a lesson on eggs. In this lesson, students will be asked to hypothesize from what state to what state will an egg become if fried. I will then ask students to think about ways to reverse the state of matter. I want students to investigate states of matter that are not easily reversed. This will allow students to discover that the unfolding of proteins is not as easily reversed. I will use hands-on demonstrations to illustrate the point. It will involve unraveling string, tangling it, and asking students to try to put it back together neatly. This type of hands-on, visual representation will help students conceptualize the process in a more concrete way. “Denaturation of proteins involves the disruption and possible destruction of both the secondary and tertiary structures. Since denaturation reactions are not strong enough to break the peptide bonds, the primary structure (sequence of amino acids) remains the same after a denaturation process.”6
Heat can be used to disrupt hydrogen bonds and nonpolar hydrophobic, tending to repel or fail to mix with water, interactions. This occurs because heat increases the kinetic energy and causes the molecules to vibrate so rapidly and violently that the bonds are disrupted. The proteins in eggs denature and coagulate during cooking. Other foods are cooked to denature the proteins to make it easier for enzymes to digest them. Medical supplies and instruments are sterilized by heating to denature proteins in bacteria and thus destroy the bacteria.6
Comments: