[填空题]
The enzyme pepsin hydrolyww9q 8y *5kzr2: dixhwses proteins to r0z(oms:yj x 7z,l ttiauyx9+ *elease peptides in the stomach. A study was cs u:+xt9zl(tx ai,y0om7j * yzarried out to determine the effect of increasing substrate concentration on enzyme activity at a constant temperature of $30{\circ}C.
1.Describe the trends shown by the graph.
2. 1.Outline why it is important that temperature is kept constant in this experiment.
2.State one factor other than temperature that would need to be controlled in this experiment.
3.Suggest a method that can be used to maintain a constant temperature in this experiment.
3.Calculate the rate of reaction during the first 4 minutes when the enzyme pepsin is exposed to 5 mM of protein. Make sure you show your working.
4.Explain the observed results.
