SME
Grade 9 Science · Problem type
Enzyme activity by temperature
Use this to record or read how fast an enzyme works at each temperature.
Record and look
20
45
80
100
60
10
10 °C
20 °C
30 °C
37 °C
45 °C
55 °C
10 °C
20 °C
30 °C
37 °C
45 °C
55 °C
Reaction rate (% of the fastest)
20
45
80
100
60
10
Activity rises to a peak near 37 °C, then falls as heat changes the enzyme’s shape: it denatures.
Tap a bar at the height you want.
Assumptions
•
A human enzyme: it lowers the activation energy of a reaction and is not used up.
•
Warmth speeds the molecules up, but too much heat changes the enzyme’s shape so its active site no longer fits.
← Previous lesson
Photosynthesis, respiration or fermentation?
Next lesson →
The cell cycle and its control, cancer, mitosis and meiosis
Topic check
See what you know: 5 questions on this topic
New questions each time. Pass to mark it complete.
Refresh
Related lessons
Cellular energy: ATP, photosynthesis and cellular respiration
Main lesson
The photosynthesis equation
Use this for “How many CO₂ molecules make 2 glucose molecules, and are the atoms conserved?”
The stages of cellular respiration
Use this for “Where does each stage of respiration happen, and which makes the most ATP?”
Photosynthesis, respiration or fermentation?
Use this for “Which process makes bread dough rise?”