Enzyme Action Flashcards
What are enzymes
Globular proteins that act as catalysts
What do enzymes do
They speed up reactions that already occur
What’s the activation energy
The minimum amount of energy required to activate the reaction in this way
What doe enzymes do to the activation energy, how does this help sustain life
Enzymes work by lowering the activation energy level. They allow reactions to take place at lower temps
It enables some metabolic processes to occur rapidly at the human body temp of 37 degrees. Which is relatively low in terms of reactions - without enzymes these reaction would proceed too slowly to sustain life as we know it
How is an enzyme substrate complex made
The molecule which the enzyme acts is called the substrate, this fits nearly into the active site (region of the enzyme that’s functional) and forms an enzyme substrate complex
How is the substrate molecule held within the active site
By bonds that temporarily form between certain amino acids of the active site and groups of the substrate molecule
What’s the induced fit model
The enzyme is flexible and can mound itself around the substrate. The enzyme has a certain general shape, but this changes in the presence of the substrate molecule. The strain distorts a particular bond or bonds in the substrate and consequently lowers the activation energy needed to break the bond.
Explain why enzymes are effective in small quantities
They are not used up in the reaction so can be used repeatedly
Outline why changing one of the amino acids that make up the active site could prevent the enzyme from functioning
The changed amino acid may be one that forms new H bonds with other amino acids. If the new amino acid does not form hydrogen bonds the tertiary structure of the enzyme will change, including the active site, so that the substrate may no longer fit
Explain why changing certain amino acids that are not part of the active site also prevents the enzyme from functioning
The changed amino acid may be one that forms hydrogen bonds with other amino acids. If the new amino acid does not form hydrogen bonds the tertiary structure of the enzyme will change, including the active site, so that the substrate may no longer fit
