biology - enzymes Flashcards
substrate
the molecule that reacts wih an enzyme
induced fit
where active site changes shape slightly as it binds to the substrate so it fits better
what factors affect enzyme action?
- temperature
- substrate concentration
- pH concentration
catalyst
something that speeds up the rate of a reaction
denature
- where the active site of an enzyme changes shape
- this means the reaction cannot occur as it is no linger complementary
enzymes
- a protein
- acts as a biological catalyst to accelerate a reaction
- lowers the activation energy
- enzymes can be reused
- helps facilitate biochemical reactions in our bodies
activation energy
the minimum energy required for a reaction to take place
what happens to the enzyme as the temperature increases?
as the temp increases…
- the rate of reaction also increases
- the molecules of more kinetic energy, so there will be more frequent, successful collisions between the substrate and enzyme, eventually reaching its optimum teperature
- higher temperature = bonds eventually become strained and break once it passes optimum temperature, so the enzymes will denature and the temperature drops to 0
optimum temperature
the temperature at which the enzyme has the highest rate of activity
active site
something that binds to the substrate
complementary
where the substrate and active site that perfectly fit together because they are shape specific
lock and key analogy
where thereis only one substrate fits each enzyme because they are shape specific
what happens to enzymes when the substrate concentration increases?
- as the substrate concentration increases,the rate of reaction also increases
- the increased number of substrate particles lead to a higher collision rate with the active sites of enzymes
- as the substrate concentration increases even more, rate of reaction remains costant BECAUSE at high substare concentrations, many active sites are already occupied
what happens to the temperature as the pH increases?
- low pH = rate is low (denatured enzyme)
- mid pH = rate increases to optimum pH
- high pH = rate is low (denatured enzyme)
what’s the difference between catabolic and anabolic enzyme-controlled reactions?
- anabolic reactions use energy to build complex molecules from simpler organic compounds (e.g., proteins from amino acids + carbohydrates from sugars)
- catabolic reactions break complex molecules down into simpler ones, releasing chemical energy
