Chapter 5: Enzymes and Their Functions

A substance that speeds up a chemical reaction without being consumed itself.

Proteins that act as biological catalysts, speeding up specific chemical reactions within living organisms.

Enzymes are crucial for life because they enable reactions to occur at speeds necessary for survival. Without them, reactions would be too slow for cells to function.

An enzyme's active site has a specific shape that complements the shape of its substrate. This fit allows them to bind together, forming an enzyme-substrate complex.

Enzymes are affected by temperature. Optimal temperatures allow for the best fit between enzyme and substrate, leading to increased reaction rates. Extreme temperatures can cause denaturation, altering the enzyme's shape and disrupting its function.

Enzymes are also affected by pH. Each enzyme has an optimal pH range where it functions best. Extreme pH values can disrupt the enzyme's shape and denature it, reducing its activity.

The active site of an enzyme is a specific region that binds to the substrate. This binding forms an enzyme-substrate complex, allowing the reaction to proceed.

Enzymes are highly specific, meaning each enzyme typically acts on only one or a small group of related substrates. This specificity is determined by the shape and fit of the active site.

The temperature at which an enzyme exhibits its maximum activity.

The pH value at which an enzyme shows its highest activity.

Enzymes are biological catalysts that speed up biochemical reactions in living organisms without being consumed in the process.

Enzymes have a specific region called the active site where the substrate binds. This site is precisely shaped to fit the substrate, allowing the enzyme to act on it.

Increased temperature generally leads to a faster enzyme reaction rate because molecules move faster, increasing collisions and hence increasing the chance of the enzyme successfully interacting with its substrate.

At excessively high temperatures, enzymes lose their 3D shape and become inactive, losing their catalytic ability. This inactivation is irreversible.

Enzymes in seeds catalyze the breakdown of stored insoluble food, such as starch and proteins, into soluble forms that the developing embryo can use for growth.

Enzymes in biological washing powders break down the insoluble molecules of stains into soluble molecules, making them easier to wash away with water.

Lipases are enzymes that break down fats (lipids) into fatty acids and glycerol. This process helps remove greasy stains from clothes.

Proteases are enzymes that break down proteins into smaller units called amino acids. This is important for removing protein stains, like blood stains.

Biological washing powders containing enzymes help save energy by avoiding boiling clothes. They are effective in removing stains without damaging clothes.

Pectinase, an enzyme used in juice making, breaks down pectin, a substance found in plant cell walls. This makes it easier to extract juice, increases juice volume, and clarifies the juice.

Proteases break down proteins in baby food into smaller units called amino acids. This makes the food easier for babies to digest because their digestive systems are not fully developed.

Amylase breaks down starch into maltose, a type of sugar used in sweet making. Isomerase converts glucose into fructose, a sweeter sugar that is better tolerated by diabetics.

Lactase breaks down lactose, a sugar found in milk, into glucose and galactose, which are easier to digest. This helps individuals with lactose intolerance.

Rennin is an enzyme that clots milk, the initial step in cheese making. This enzyme is important for creating a solid curd, which is further processed to make cheese.