PAG 4 Rates of enzyme controlled reactions Flashcards
outline the investigation into the effects of factors on enzyme activity
react enzyme and substrate in a conical flask which is attached to a gas syringe which can be used to measure the volume of gas produced
what is a suitable control for an investigation into enzyme activity?
seeing what happens to a substrate when no enzyme is used
what is the independent variable in this investigation?
what you are investigating the effect of on enzyme activity:
temperature
pH
enzyme conc
substrate conc
what is the dependant variable in this investigation?
the volume of gas produced
or
enzyme activity
what is controlled in this investigation?
the variables which are not being assessed:
temperature
pH
enzyme conc
substrate conc
how might temperature be controlled?
using a water bath
all test tubes placed in same water bath
KEEPS TEMPERATURE CONSTANT
how might pH be controlled?
using a pH buffer solution
why might you use a white tile in an enzyme experiment?
to make a colour change more visible
why may a student repeat this investigation three times?
to improve the reliability by allowing you to produce a mean and identify any anomalies
can be used in a stats test
what would the optimum temperature be shown as?
a 5 degree range
what ways can a more accurate result for optimum temperature be found?
reducing the intervals of the data
use a colorimeter to get a quantitative value which is numerical
what are the benefits of a quantitative value?
less prone to bias or human error
what does standard deviation?
the spread of data around the mean
if the units for rate are s-1 what does that indicate?
1/T has been used to calculate the rate
what does a low standard deviation show?
higher precision
less spread of data around the mean
