Excercise 8 Bio

Enzyme / Catalyst

Biological protein catalysts that speed up metabolic chemical reactions without being permanently consumed in the process

Substrate

The specific reactant molecule upon which an enzyme acts to produce one or more distinct products

Active Site

The specific 3D region on an enzyme where substrate molecules bind via an induced fit mechanism.

Denaturation

Loss of an enzyme's tertiary structure and active site conformation, destroying catalytic function due to extreme heat or pH

Enzyme Inhibitor

A chemical agent (competitive or noncompetitive) that reduces or prevents enzyme-substrate binding and activity

Conformation

Protein enzymes have specific 3D shapes that determine their function, influenced by interactions between amino acids.

Hydrolysis

A chemical reaction that involves the breaking of a bond in a molecule using water, often resulting in the splitting of larger molecules into smaller units.

Variable

A factor in an experiment that can change and affect the outcome. Variables can be independent, dependent, or controlled.

Product

The outcome of a chemical reaction, resulting from the transformation of reactants by enzymes or other catalysts.

Metabolism

How cells use and store energy and it is the sum of all chemical reactions that occur inside the cell

Amylase Hydrolysis Reaction

The enzymatic breakdown of starch (a polysaccharide substrate) into maltose (a disaccharide product) using water (hydrolysis)

Reagent Used in the Starch Test

Iodine solution ($\text{I}_2\text{KI}$), which changes color in the presence of starch.

Positive Outcome for Starch Detection

A positive starch test yields a blue-black color (indicating unhydrolyzed starch and low amylase activity)

Assessing Amylase Activity via the Starch Test

A shift from blue-black to amber color indicates that starch has been hydrolyzed by active amylase over time. More time means more time for starch to break down

Effect of Freezing/Cold ($0^\circ\text{C} - 10^\circ\text{C}$) on Enzyme Activity

Slows molecular motion and lowers collision frequency, resulting in minimal activity that is reversible upon warming while native conformation is preserved.

Effect of Boiling/Extreme Heat ($70^{\circ}\text{C}-100^{\circ}\text{C}$ ) on Enzyme Activity

Causes violent thermal vibrations that disrupt chemical bonds, leading to irreversible denaturation and total loss of activity.

Effect of 37 degrees celcius on Enzymes

Enzyme activity is typically optimal at $37^\text{C}$, as this temperature enables proper molecular motion and optimal collision frequency, enhancing reaction rates without denaturing the enzymes.

Effect of pH Extremes on Enzyme Function

Alters ionic charges on amino acid side chains at the active site, disrupting tertiary structure and causing denaturation. PH 7 works best for it.

Effect of Heavy Metals like Copper ($\text{Cu}^{2+}$) on Amylase Activity

Acts as an inhibitor that alters active site conformation or interferes with substrate binding, decreasing or inhibiting amylase activity.

Negative Outcome for Statch Detection

a negative starch test yields an amber/yellow color (indicating starch hydrolysis and high amylase activity).