PART 1 MULTIPLE CHOICE SECTION

Transcription

1 Name: Total: / 54 = % = TOPIC 3 TEST PART 1 MULTIPLE CHOICE SECTION 18 marks 1. Which of the following substances are organic? I. Lipids II. III. Water Carbon dioxide A. I only B. II and III only C. I and II only D. I, II and III 2. What role does iron play in living organisms? A. As a component in nucleic acids B. As a component of lipids C. As a component of carbohydrates D. As a component of proteins 3. What is one role of the element phosphorus? A. It forms part of the structure of amino acids. B. It forms part of the structure of fatty acids. C. It forms part of the structure of ribose. D. It forms part of the structure of nucleotides.

2 4. Which of the following features are correct for hydrogen bonding? I. It is involved in the cohesion of water. II. III. It results in the thermal properties of water. It is a bond within the water molecule. A. I and II only B. II and III only C. I and III only D. I, II and III 5. What is a role of carbohydrates in animal cells? A. As channels for passive transport B. As enzymes C. As energy storage D. As components of the animal cell wall 6. What is the maximum number of fatty acids that can be condensed with glycerol? A. One B. Two C. Three D. Four 2

3 7. Which of the following terms correctly describe(s) the molecule above? I. Monosaccharide II. III. Glucose Component of triglyceride A. I only B. I and II only C. II and III only D. I, II and III 8. Which type of molecule is shown in the diagram below? A. Peptide B. Carbohydrate C. Lipid D. Nucleic acid 3

4 9. What is denaturation? A. A structural change of a protein that results in the loss of its biological properties B. A change in the genetic code of an organism C. A change in the amino acid sequence of a protein causing a disruption of its 3D shape D. The process by which amino acids are broken down and ammonia is released 10. What happens as an enzyme becomes denatured? A. The enzyme works faster. B. The enzyme works slower. C. The enzyme can perform a new role. D. The enzyme can make the reverse reaction proceed faster. 11. Which of the following graphs shows the relationship between substrate concentration and enzyme activity with a fixed concentration of enzyme? 4

5 12. Which of the following will cause an enzyme to permanently lose its properties? I. Hydrolysis II. Freezing to 20 C III. Dissolving it in water A. I only B. II only C. I and II only D. I and III only 13. How do cells capture the energy released by cell respiration? A. They store it in molecules of carbon dioxide. B. They produce glucose. C. The energy is released as pyruvate. D. They produce ATP. 14. Which of the following processes produces CO 2? I. Glycolysis II. Alcohol (ethanol) fermentation III. Lactic acid production A. I only B. II only C. I and II only D. I, II and III 5

6 15. Which row in the table describes the first stage of cellular respiration? Substrate Location Product Product A. pyruvate mitochondria oxygen water B. pyruvate cytoplasm carbon dioxide ATP C. glucose mitochondria pyruvate water D. glucose cytoplasm pyruvate ATP 16. What is the correct sequence of chemicals produced in the anaerobic respiration pathway? A. Lactate pyruvate ethanol B. Ethanol pyruvate glucose C. Glucose lactate pyruvate D. Glucose pyruvate lactate 17. What is the source of the oxygen released into the air as a product of photosynthesis? A. Chlorophyll B. Carbon dioxide only C. Water only D. Both water and carbon dioxide 18. Which type of light is least useful for photosynthesis in terrestrial plants? A. Blue B. Green C. White D. Red 6

7 PART 2 SHORT & EXTENDED RESPONSE SECTION 26 marks 19. (a) State the main photosynthetic pigment in plants. (b) State the two materials used to convert carbon dioxide to organic molecules in plants. (2) (Total 3 marks) 20. Compare the use of carbohydrates and lipids in energy storage. (Total 5 marks)

8 21. Outline the role of hydrolysis in the relationships between amino acids, dipeptides and polypeptides. (4) Explain enzyme-substrate specificity (3) 8

9 23. Describe the use of biotechnology in the production of lactose-free milk. (6)

10 24. Compare how pyruvate is used in human cells when oxygen is available and when oxygen is not available. (5)

11 2 PART 3 DATA ANALYSIS SECTION 10 marks 25. There are many abiotic factors that affect the rate of photosynthesis in terrestrial plants. Wheat is an important cereal crop in many parts of the world. Wheat seedlings were grown at three different concentrations of carbon dioxide (in parts per million) and the rate of photosynthesis was measured at various light intensities. Rate of photosynthesis / l CO min key: 1300 ppm CO 500 ppm CO 280 ppm CO Light intensity / 10 lumen m 2 [Source: Adapted from J P Kimmins, 1997 Forest Ecology, (2nd edition) page 161] (a) Describe the relationship between the rate of photosynthesis and light intensity for wheat seedlings grown at a CO 2 concentration of 500 ppm. (2) (b) 11

12 (b) Outline the effect of CO 2 concentration on the rate of photosynthesis of the wheat seedlings. (3) (c) The normal atmospheric concentration of CO 2 is 370 ppm. Deduce the effect of doubling the CO 2 concentration to 740 ppm on the growth of wheat plants. (2) Leaf area and chlorophyll levels were measured in sun leaves and shade leaves of Hedera helix (English Ivy) and Prunus laurocerasus (Cherry Laurel). Sun leaves developed under maximal sunlight conditions while shade leaves developed at reduced sunlight levels in the shadow of other leaves. Species Leaf Type Chlorophyll/ g ml -1 Leaf Area/ cm 2 Ivy Shade Sun Laurel Shade Sun [Source: D Curtis, Plant Ecology independent project, 1990] (d) Calculate the percentage increase in the amount of chlorophyll in shade leaves of ivy compared to sun leaves of ivy 12

13 (e) Suggest a reason for the differences in chlorophyll concentration and leaf area in sun and shade leaves in these two species. (2) (Total 10 marks) 13