HKCEE BIOLOGY | 1.3 Cell activities | P.1 1. 1990/II/15 Enzymes can not work properly at high temperatures because A. they are catalysis B. they are proteins C. they work on specific substances D. they work best at 37°C 2. 1990/II/45 Which of the following shows the correct end product of the corresponding metabolic process occurring in a mammal? Metabolic process A. breakdown of amino acids B. breakdown of red blood cells C. breakdown of glucose aerobically D. breakdown of glucose anaerobically End product nitrogen bile salts water alcohol 3. 1992/II/7 Which of the following graphs shows the reaction rate of a hot mixture of starch and amylase when it is cooled down from 80°C to 0°C 4. 1993/II/8 The following table shows the percentage changes in mass of four groups of potato strips which have been immersed separately in four different solutions (I to IV) for one hour : Solution Percentage change in mass I + 5% II - 5% III - 3% IV 0% Which of the following conclusions can be drawn? A. B. C. D. Solution I has the highest water potential. Solution II has a higher water potential than solution III. Solution IV has the lowest water potential. Solution IV is distilled water. 4 HKCEE BIOLOGY | 1.3 Cell activities | P.2 5. 1993/II/10 Questions 5 and 6 refer to the experimental set-up shown below: What will happen to the liquid levels in tubings (1) and (2) after one hour? Tubing (1) A. fall B. fall C. rise Tubing (2) fall rise rise D. fall rise 6. 1993/II/11 Which of the following graphs shows the likely changes in liquid level in tubings (2) and (3)? 7. 1994/II/50 The graph below shows the effect of temperature on the activity of salivary amylase: Which of the following statements concerning salivary amylase is correct? A. It is denatured at 0ºC. B. C. D. Its activity increases steadily with a rise in temperature. It is most active at 60ºC. It is killed at 80ºC. 5 HKCEE BIOLOGY | 1.3 Cell activities | P.3 8. 1995/II/5 The diagram below a set-up to study the effect of amylase on starch. After 3 hours, water in the beaker was heated with Benedict's solution and a red precipitate appeared. Which of the following can deduced from the above experiment? A. Glucose was form the digestion of starch. B. Starch could not pass though the dialysis tubing. C. The dialysis tubing allowed reducing sugar to pass through. D. The water potential of the solution in the dialysis tubing increased. 9. 1995/II/7 Question 9 and 10 refer to the graph below which shows the change in mass of a potato strip in distilled water at 20°C : The rate of the osmosis is the highest between A. hour 0 and hour 0.5 B. hour 0.5 and hour 1.0 C. hour 1.0 and hour 1.5 D. hour 1.5 and hour 2.0 10. 1995/II/8 Which of the following is a correct description of the potato cells between hour 2 and hour 3? A. The cells were turgid. B. The cell vacuole burst. C. The cell wall was impermeable to water. D. The cell membrane was fully permeable. 6 HKCEE BIOLOGY | 1.3 Cell activities | P.4 11. 1997/II/3 Which of the following processes is carried out by osmosis? A. The upward transport of water in the xylem. B. The reabsorption of glucose in the kidney tubules. C. The return of tissue fluid into the blood capillaries. D. The uptake of mineral salts from the soil into the root. 12. 1999/II/8 Questions 12 and 13 refer to the diagram below, which shows the initial condition of two set-ups : After 1 hour, the liquid level in the capillary tube of set-up 2 is much higher than that of set-up 1. Which of the following is a probable reason for this result? A. Solution 1 has a lower water potential than solution 2. B. The dialysis tubing of set-up 1 is less permeable to water than that of set-up 2. C. Sugar is produced in solution 2. D. Less starch is present in solution 2. 13. 1999/II/9 Which of the following treatments might increase the rate of rise of the liquid level in set-up 2? (1) using a narrower dialysis tubing (2) using a capillary tube with a smaller internal diameter (3) raising the temperature of the distilled water from 20ºC to 30ºC A. (1) and (2) only B. (1) and (3) only C. (2) and (3) only 7 D. (1), (2) and (3) HKCEE BIOLOGY | 1.3 Cell activities | P.6 14. 2000/II/11 The table below shows the body mass of four mammals and their rate of oxygen consumption per unit body mass : Mammal Body mass (g) Rate of oxygen consumption per unit body mass (mm³ h-1 g-1) Mouse 25 1 580 Rabbit 2 200 466 Man 70 000 106 Elephant 3 800 000 67 What can be concluded from the above data ? A. Smaller mammals have a faster heart beat. B. Smaller mammals have a higher metabolic rate. C. Smaller mammals have a higher body temperature. D. Smaller mammals have a more efficient breathing system. 15. 2001/II/4 Which of the following statements about enzymes is correct? A. B. C. Enzymes are made up of proteins or fats. Enzymes are denatured at 0ºC. The optimum temperature of most enzymatic activities is 37ºC. D. The activity of most enzymes is low at 80ºC. 16. 2004/II/3 A student defines osmosis as “ the movement of water molecules from a dilute solution to a concentrated solution across a selectively permeable membrane.” This definition is inaccurate because A. solute molecules can also move along the concentration gradient. B. water molecules can also move from the concentrated solution to the dilute solution. C. it should state clearly that the membrane is not permeable to the solute molecules. D. movement of water molecules can still occur without a selectively permeable membrane. 8 HKCEE BIOLOGY | 1.3 Cell activities | P.7 17. 2004/II/15 Questions 17 and 18 refer to the diagram below, which shows a set-up used by Eric to study osmosis: If Eric carries out the investigation for four hours, what would be the change in the liquid level in the capillary tube with time? 18. 2004/II/16 Which of the following can increase the rate of rise of the liquid level in the capillary tube? (1) Raise the water temperature to 30°C (2) Use a larger beaker with more water inside (3) Use a capillary tube with a smaller internal diameter A. (1) and (2) only B. (1) and (3) only C. (2) and (3) only D. 19. 2004/II/19 Which of the following processes does not require metabolic energy? A. movement of the ovum in the oviduct. B. movement of undigested food along the colon. C. movement of oxygen from the air sacs of the lung into the blood. D. movement of amino acids from the glomerular filtrate to blood capillaries. 9 (1),(2) and (3) HKCEE BIOLOGY | 1.3 Cell activities | P.8 20. 2004/II/59 Questions 20 and 21 refer to an investigation on the enzyme catalase, which breaks down hydrogen peroxide and release oxygen. In order to show whether a certain plant tissue contains catalase or not, Joyce set up the following experiment : Joyce observed that a lot of gas bubbles were released in tube I but not in tube 2. In order to conclude that the plant tissue contains catalase, what additional steps should be taken by Joyce? (1) Test whether the gas bubbles contain oxygen (2) Set up a tube containing water and the fresh plant tissue (3) Set up a tube containing hydrogen peroxide but no plant tissue A. (1) and (2) only B. (1) and (3) only C. (2) and (3) only D. (1),(2) and (3) 21. 2004/II/60 When gas bubbles stopped coming out from tube I, Joyce added more hydrogen peroxide into the tube. She observed that gas bubbles were produced again. What can be implied from this observation about the property of enzymes? A. Enzymes can be reused. B. Enzymes are specific in action. C. Enzymes are made up of proteins. D. Enzymes can speed up chemical reactions. 10 22. 2005/II/1 Questions 22 to 24 refer to the following experiments: Two test tubes containing 5 cm 3 of hydrogen peroxide solution and 1 cm 3 of catalase solution respectively were kept at 30°C for 30 minutes. The contents of the two tubes were then mixed and maintained at the same temperature, and the amount of oxygen released was recorded for 5 minutes. The same experiment was repeated at 40°C. The results are shown below: The initial rate of oxygen production at 40°C is higher than that at 30°C because A. catalase is denatured at the lower temperature. B. oxygen is less soluble at the higher temperature. C. more active sites are present in the enzyme molecules at the higher temperature. D. the substrate molecules have more kinetic energy at the higher temperature. 23. 2005/II/2 Which of the following is a correct interpretation of the graph? A. At 30°C, the rate of reaction was higher at the 5th minute. B. At both temperatures, the amount of oxygen released in 5 minutes was the same. C. At both temperatures, the time for the decomposition of all hydrogen peroxide was the same. D. All active sites of enzymes were occupied at the end of the experiment. 24. 2005/II/3 A third experiment was carried out as before but the contents were kept at 90℃. Which of the following would best indicate the result of the experiment? 11 HKCEE BIOLOGY | 1.3 Cell activities | P.9 25. 2006/II/23 Questions 25 to 27 refer to the graph below, which shows the rates of reactions catalysed by two enzymes A and B over a range of pH values: The rates of the reactions catalysed by enzymes A and B are equal at A. pH 4 B. pH 5 C. pH 6 D. pH 7.5 26. 2006/II/24 Which of the following is a correct interpretation of the graph? A. Enzyme A is found in gastric juice. B. Enzyme B is more active than enzyme A. C. The optimum pH value for enzyme B is 1.8. D. Enzyme A is more active than enzyme B at pH 4. 27. 2006/II/25 In the above study, it is important to keep the temperature at which the reactions occur constant because A. temperature affects enzyme activity. B. the enzyme becomes inactive at low temperatures. C. the enzyme becomes denatured at low temperatures. D. temperature should be the same for control experiments. 12 HKCEE BIOLOGY | 1.3 Cell activities | P.10 28. 2007/II/7 Questions 28 and 29 refer to the following experiment : Two boiling tubes containing 5 cm 3 of hydrogen peroxide solution and 1 cm 3 of catalase solution respectively were kept at 25°C for 10 minutes. The contents of the two tubes were then mixed and maintained at the same temperature, and the amount of oxygen released was recorded for 5 minutes. The results are shown below: The line level off at the 3rd minute. Which of the following is a correct explanation for this? A. The reaction stops at the 3rd minute because catalase has been used up. B. The reaction stops at the 3rd minute because hydrogen peroxide has been used up. C. The reaction rate reaches the maximum at the 3rd minute because the amount of oxygen released is highest. D. The reaction rate reaches the maximum at the 3rd minute because there is no more increase in the amount of oxygen released. 29. 2007/II/8 The same experiment was repeated but the contents were kept at 35℃. Which of the following would best indicate the result of the experiment? 30. 2008/II/13 Questions 30 and 31 refer to an experiment about osmosis. Three strips of the same size were cut from a fresh potato and immersed into sucrose solutions of different concentration for four hours. The experiment was repeated using a potato that has already been stored for a certain period of time. The results obtained are shown in the table below: Concentration of sucrose solution Percentage change in mass of the strips (%) Fresh potato Stored potato 0 +20.0 +25.0 5 +6.0 +10.0 10 -7.0 -2.0 The dependent variable in the experiment is measured as the percentage changes in mass of potato strips because A. the final masses of the potato strips are different. B. the initial masses of the potato strips are different. C. there is a significant change in the mass of the photo strips. D. the mass can be measured accurately by using an electronic balance. 13 HKCEE BIOLOGY | 1.3 Cell activities | P.11 31. 2008/II/14 Which of the following about the interpretation of the results is correct? A. Water potential of potato after storage decreases B. decreases C. increases D. increases Explanation some starch is converted to sugars during storage some starch is used for growing during storage water is lost through evaporation during storage the permeability of cell membrane increases during exercise 32. 2008/II/35 Questions 32 and 33 refer to the graph below, which shows the results of an investigation of an enzyme reaction performed by a group of students. Which of the following is the correct explanation of the above results? A. More enzymes can be reused as the temperature increases. B. Enzyme is made up of proteins, it is denatured as the temperature increases. C. Enzyme collides with substrate more frequently as the temperature increases. D. Enzyme is inactive at low temperature and therefore there is no reaction at 0°C. 33. 2008/II/36 After the investigation, one of the students concluded that the optimum temperature of this enzyme is 40°C. However, another student disagreed with this conclusion. We can verify whether the conclusion is correct by repeating the experiment A. B. C. D. several times. with a wide range of temperature. with a smaller interval of temperature. with a greater amount of enzyme and substrate. 14
