Select a, c, d. This is a test of reagent selection. In item a, hydrogen peroxide is thermally decomposed, so it is not appropriate to explore the effect of temperature on enzyme activity and is therefore wrong. In division b, the rate of decomposition of starch in the act of starch enzymes is determined at different temperatures, depending on whether the blue is dark or blue. In item c, starch cannot be decomposed by sugar cane enzymes, so the experiment could not identify ph effects on enzyme activity and was therefore wrong. In division d, the acidic environment can damage the perin reagent, and therefore the perin reagent is not suitable for the test of ph for enzyme activity. ; 1. (2009 liaoning kocau) right chart indicates the relationship between enzyme activity and temperature. The following description is correct: () a. When the reaction temperature is moved from t2 to the most acoustic temperature, the enzyme activity is reduced b. When the reaction temperature is moved from t1 to the most accommodative temperature, the enzyme activity is increased c. Enzyme activity is higher at t2 than at t1 and therefore the preservation of the enzyme d. Enzyme activity at t2 is more suitable at t1 than at t2, indicating that the spatial structure of the enzyme at t1 is more severe; [resolution] select b. The activity of the enzyme is highest at the most appropriate temperature. High or low temperatures reduce enzyme activity significantly. The enzyme activity rises when the reaction temperature is moved from t1 to the highest temperature. High temperatures also cause the spatial structure of enzymes to be destroyed and the enzymes to permanently inactivate. The low temperatures around 0 °c, while significantly reducing the activity of the enzymes, stabilize the spatial structure of the enzymes, recover the activity of the enzymes at the appropriate temperature, and the enzymes are suitable for preservation at low temperatures. 2. (n roll 2012) in order to explore the effects of ph on human saliva starch activity, a student designed the following experimental step: add ph 5. 0, 6. 0, 7. 0, 8. 0 and 9. 0 respectively to the test tubes, and add 1 ml to the suitable buffer fluid of 1% mass. 2 a saliva dilution of 1 ml at an appropriate concentration is added to each test tube, and is wavered. 3 place five test tubes in a hot bath at 70 °c with the same temperature protection time and appropriate. Four remove the tubes and add two ml of the fungus reagents. 5 observe the colour of the test tube solution and the most appropriate ph for saliva starch enzymes by light colour. ; for two errors in the above-mentioned experimental step, please correct the correction and explain the reasons for the correction (without regard to the concentration and addition of the reagent, the ph gradient and the number of repeats of the experiment), so that the test can be correctly expected. (1)? (2)? ; [resolution] (1) can maximize the catalytic activity of enzymes only at the most appropriate temperature. The maximum temperature of the saliva dust enzyme is 37 °c, and at 70 °c, the effect of ph on human saliva starase activity is disrupted by the loss of activity due to high temperature. (2) in boiling water baths, the reagents of pelicans react with reduced sugars with a red-brick deposition. ; answer? ? (1) three corrections: place five test tubes in a 37 °c hot bath with the same temperature protection time and appropriate. Reason: the maximum temperature of saliva starase is 37 °c. At 70 °c, the effect of ph on human saliva starase activity is disrupted by the loss of activity due to high temperature (2) 4 correction: remove the test tubes, add 2 ml to the funnel reagent, shake them, place them in a boiled cup with open water and heat them with alcohol lamps. Reason: the pelican reagents react in boiling water baths; 3. (2011 jiangsu gacau) in order to explore the effects of acid enzymes on the growth and digestive enzyme activity, researchers designed and carried out experiments, with the following steps and results: 1 stamping of the acetfish: 14d raised from the sea-capped shoalfish seedlings in floating sea-water net box, fed with ordinary feed, provided for. 2 forage formulation: 200 mg of acid enzyme per kilogram of general feed is added and formulated into enzyme feed; and common feed and enzyme feed are made into particles of the same size and stored after drying. ); 3-hicked fish breeding: select a random group of healthy, well-sized herds to be fed in floating seanet boxes with the same specifications, with a 60-tail/box density. A regular feed of appropriate amounts is delivered to the control group and an equivalent feed of enzymes is fed to the experimental group. 4 scaled and recorded: 20 tails of catfish are randomly weighed from each net box after eight weeks of feeding. The results showed an average increase of 859. 3 per cent and 947. 2 per cent for control groups and experimental groups, respectively. ;5 prepare a digestive enzyme sample in the intestinal tract of the catfish and separately measure the digestive enzyme activity, as shown in the table below. ; on the basis of the above-mentioned experiment, answer the following questions: (1) the main reason chosen in step 1 for the use of the scabies rather than for their formation is that the pre-test domestication was intended. (2) the drying of prepared feed in step 2 requires special attention because of the reasons. (3) the irrelevant variables that should also be controlled in step 3 are mainly those. (4) the preliminary conclusion of this experiment is that: (5) presumed and justified the diet of the herring: ; [decomposition] the main reason for the selection of fish seedlings for the experiment instead of forming bodies is slow growth and the results of the experiment are not significant; pre-test domestication is intended to adapt the herring to the experimental breeding environment. When drying well-formulated feed, particular attention is to be paid to the fact that the temperature is not too high and that high temperatures can cause acid enzymes to become less active. Non-relevant variables in the experiment, such as water temperature, salinity and dissolved oxygen, may affect the experiment. The preliminary conclusions of the experiment were that the introduction of acid enzyme feed could boost the growth of the larvae's larvae, and that the enzyme could increase the activity of protein enzymes in the intestinal tract, with less impact on the activity of fat enzymes and starch enzymes in the intestinal tract. Based on the results of the experiments, it can be assumed that the herring is carnal, as its protein enzyme activity is significantly higher than that of fatty enzyme and starch enzymes. The answer is: (1) slow growth of the adult body and the experimental effects do not clearly adapt the herring to the experimental breeding environment (2) the temperature is not too high to cause the acid enzyme to deteriorate (3) water temperature, salinity and dissolved oxygen (4) feed with acid enzyme can contribute to the growth of herring's larvae; acid enzyme can increase the activity of protein enzymes in the intestinal tract, with less impact on the activity of fatty enzymes and starchase in the intestinal tract (5) carving, with protein enzymes in the intestinal tract being significantly more active than fatty enzyme and starchase; 4. (2010 hainan gaocau) has been experimented with the effects of nacl and cuso4 on the activity of saliva-polyticase, with the experimental steps and results shown in the table. Please answer: (i) the role of the buffer in the experiment is . (2) analysis of the results of the experiments shows that the ion that has an impact on enzyme activity is , in which the ion that has inhibitive effects on enzyme activity is and the ion that contributes to enzyme activity is . (3) the purpose of setting test tube 4 in the experiment is ; the purpose of setting test tube 3 is . (4) in the above-mentioned experiments, the colours in test tubes 1 to 4 are , , , , , , if they are tested in replacement of iodised solution with pelican reagents. According to the results of the above-mentioned experiments, it was not possible to add pelican reagents to the temperature during the operation because . ; [decomposition] this question examines the conditions affecting enzyme activity, as follows: (1) ph can affect enzyme activity, and in order to ensure a single variable, ph buffer must be used to maintain ph persistence. (2) (3) the fourth test tube is in contrast. The 3rd test tube compared to the 4th test tube, na+ and so42 - had no impact on the catalytic activity of saliva starchase; the 1st test tube compared to the 4th test tube, cl - contributed to the activity of the enzyme; the 2nd test tube compared to the 4th test tube, cu2+ inhibited the activity of the enzyme. (4) the second test tube, which has no brick red because of its inhibition of enzyme activity by cu2+, and the starch has not been dissolved; the first test tube, which has a dark brick red by cl-enzymic activity and the starch has been fully decomposition; and the third and the fourth test tube has been decomposition, but not completely, so the light brick red。(i) maintaining ph stability in reaction fluids (other reasonable answers may also be available) (2) cl- and cu2+ cl-(3) determine if na+ and so42-activated saliva dust enzymes are affected (other reasonable answers may also be available) (4) deep brick red, no brick red (or blue) light brick red, light brick red (other reasonable answers may also be available) cu2+, which inhibits the activity of saliva dust enzymes in the pelican reagent
