enzymes are biological ___ that speed up reactions by breaking larger molecules down (digesting them)
catalyst
2 of 20
amylase breaks down starch into...
glucose
3 of 20
what factors effect how fast the amylase breaks down the starch?
concentration of amylase, temp, pH
4 of 20
What temp do enzymes tend to work best at?
body temp - 37 degrees
5 of 20
to test the effect of pH on amylase we first place buffer solution in a test tube. why buffer solution?
it has a certain pH and maintains it's pH even when environment changes
6 of 20
we then add starch, then amylase. what6 do we need to do as soon as we've added the amalse?
start stop watch
7 of 20
to test if any starch remains in the test tube every 30 seconds, we use a spotting tile filled with a drop of ___ (what's used to test for starch...?)
iodine
8 of 20
we can then insert solution from test tube after 30 seconds to spotting tile with a pipet or glass rod. what colour should the iodine + solution turn if there is starch present?
black / blue
9 of 20
repeat process every 30 seconds to see how long it takes for starch to be digested. how would we know when there is no starch present?
there would be no colour change
10 of 20
the experiment is repeated with different...
pH values
11 of 20
what's the independent variable in this experiment?
pH
12 of 20
How do we control the pH?
Use buffer solution
13 of 20
what's the dependent variable?
time taken for amylase to digest starch
14 of 20
how do we measure this?
use continuous sampling technique
15 of 20
what are the control variables?
volume of liquids, temp
16 of 20
how can we keep the temp same?
water bath
17 of 20
how can we keep the volumes the same?
measure with pipette
18 of 20
what factors could effect accuracy of results? (observations? uncertainty?)
results depend on human judgment (observing colour change). results could be anywhere between the 30 second intervals.
19 of 20
how could we increase accuracy?
test in smaller intervals. use more pH values (instead of 5, 6, 7 use 5, 5.5. 6 ect)
20 of 20
Other cards in this set
Card 2
Front
enzymes are biological ___ that speed up reactions by breaking larger molecules down (digesting them)
Back
catalyst
Card 3
Front
amylase breaks down starch into...
Back
Card 4
Front
what factors effect how fast the amylase breaks down the starch?
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