BioChem 2.5 Enzymes Flashcards
What is an enzyme?
An enzyme is a biological catalyst which speeds up te rate of reactions.
What is an active side?
All enzymes have an active side whose shape is complementary to the substrate molecule(s). Enzymes are specific meaning that they can only speed the reaction of a specific substrate.
How do enzymes work?
- Enzymes are shaped complementary to a substrate. 2.Substrate moves into the enzyme and locks in. 3.An enzyme substrate complex is formed. 4.A chemical reaction happens. The substrate is turned into products. Enzyme may act as catabolic or anabolic. 5. Products move out of enzyme 6. Enzyme is ready to accept another substrate molecule
Explain enzyme-substrate specificity.
Enzymes’ active side and substrates have complementary shapes, so that the substrate fits into the enzyme like a key. This is called a lock and key model of enzyme action. A different kind of substrate cannot fit as the shape needs to fit perfectly. This makes enzymes specific. They are specific in order to make different products that the protein is assigned to.
If an enzyme is a protein, is it fibrous and globular?
Enzymes are globular proteins.
What happens to an enzyme when in extreme pHs or high temperatures?
The enzyme will be denatured. Denaturing refers to a permanent structural change in a protein that results in a loss of its properties Denaturing causes a change of shape of the active side of the enzyme which means it will not function anymore.
Draw a graph to show the expected effects of temperature on enzymes.
As temperature increases, relative activity increases until the enzymes is denatured where it will rapidly fall.
Draw a graph to show the expected effects of pH on enzymes.
As pH increases towards its optimum pH, relative activity increases. As pH increases away from its optimum pH, activity decreases.
Draw a graph to show the expected effects of substrate concentration on enzymes.
As concentration increases, activity increases to its point of saturation. Beyond the point of saturation, the increase in concentration remains constant.
Explain the effects of temperature on enzymes
As temperature increases, increases due to collision theory. As higher temperatures cause more movement, collisions occur more frequently. As temperature increases beyond the optimum temperature, the enzyme will denature causing activity to slow down rapidly.
Explain the effects of pH on enzymes
As the pH increases, enzymes are closer to their optimum pH where they work most efficiently. As pH increases beyond the optimum pH, the enzyme slowly starts to denature, slowing the activity.
Explain the effects of substrate concentration on enzymes.
When substrate concentration increases, collision frequency increases as there are more substrates enzymes can react with. After reaching point of saturation, activity can no longer be increase regardless of increase in substrates, as all enzymes are bound and reacting at maximum rate
What are immobilized enzymes?
Immobilized enzymes are enzymes which are restricted from movement and are in a fixed space.
How are immobilized enzymes used in industry of production?
Immobilized enzymes are used in many industries. 1. Production of lactose free milk by having the enzyme lactase. 2. Production of sodas where glucose isomerase is used to break glucose to fructose to make the drinks sweeter 3. Production of fruit juice to break down pectin which makes it cloudy with the enzyme pectinase. 4. Biological washing powder contains protease, amylases and lipases. This makes it effective at breaking down food stains in low temperature that saves household costs.
How is lactase used in the production of lactose free milk?
Lactase breaks down lactose into glucose and galactose This creates lactose free milk which can be enjoyed by consumers around the world, regardless of whether they are lactose intolerant or not.
