B5 - Enzymes Flashcards
What are enzymes?
Proteins that are involved in all metabolic reactions, where they function as biological catalysts
What are catalysts?
substances that speed up chemical reactions without being used up
where do chemical reactions take place?
active site
what is a substrate?
substance acted on by an enzyme. substrate molecules become product molecules
what does it mean that enzymes are specific?
each enzyme only binds to one type of substrate molecule
what are the 5 steps to breaking down a large molecule?
1) a big substrate molecule fits into the active site
2) enzyme-substrate complex is formed
3) a bond in the substrate breaks
4) 2 smaller product molecules are made
5) the enzyme can then go on the break down another substrate
what are the 5 steps to producing a bigger molecule?
1) substrate molecules fit side by side into the active site
2) enzyme substrate complex is formed
3) substrate molecules are brought together so that they can form a bond
4) a bigger molecule is made
5) the enzyme can then be used again with another set of substrate molecules
what are 6 ways to improve the investigation of catalase concentration in different tissues?
-do it one at a time
-test tubes are same width
-more repeats
-use gas syringe/collect gas over water
-same temperature (put in water bath)
-try different cells (plant and animal)
what happens to the kinetic energy as the temperature increases?
kinetic energy of the molecules increases
what happens if molecules collide more?
enzyme and substrate molecules come together more often and more enzyme substrate complexes are formed
what is the optimum temperature?
the temperature where the rate of reaction is highest.
why does the rate of reaction decreases once the optimum temperature is passed?
the substrate can’t bind anymore because the enzyme is denatured and the active site changes shape
where in the optimum point does the enzyme’s rate of action get effected? (pH)
increase in pH above or below optimum point
what happens to the enzyme if the change in pH is extreme?
enzyme will become denatured
why does the pH make the enzyme denatured at certain points?
change in pH affects interactions between the amino acids in a chain and may make the enzyme unfold, which changes the shape of the active site, so enzyme-substrate complexes cannot be formed. The more significant the change in pH, the more the bonds break (changes shape more)
