1. Studies are taking place to assess the benefits to dental health of adding fluoride to drinking water, a process known as mass medication. The Health Minister has urged consideration of fluoridation, particularly in deprived areas where dental care is poor. Fluoride can occur naturally in the water because of fluoride containing minerals. Fluoride, if in the water, improves dental health by up to 50 percent. Even so, fluoridation should not take place. A campaign leader opposed to fluoridation has spoken of her experiences of living in a fluoridated area of the USA. She experienced feelings of apathy and depression; her 2 year old son showed autistic tendencies and had white flecks on his teeth. These symptoms disappeared when they returned home from the USA. Which one of the following is an underlying assumption of the argument above?
2. Climate scientists in Greenland studying patterns of plant growth have suggested that the early arrival of spring in the Arctic threatens to drive down populations of migrating animals such as caribou. However, comparable studies elsewhere show that their fears are unfounded. A recent study of great tits in Oxfordshire showed the birds are capable of adapting to climate change better than many scientists expected. Over the past half century, the birds have brought forward the date they lay their eggs by two weeks, so that young are born when plant-eating grubs are most plentiful. Which one of the following is an underlying assumption of the above argument?
3. Now, it might be thought an amazing coincidence if Earth were the only planet in the galaxy on which intelligent life evolved. If it happened here, the one planet we have studied closely, surely one would expect it to have happened on a lot of other planets in the galaxy – planets we have not yet had the chance to examine. This objection, however, rests on a fallacy: it overlooks what is known as an 'observation selection effect', so it wouldn't be such a coincidence. Whether intelligent life is common or rare, every observer is guaranteed to originate from a place where intelligent life did, in fact, arise. Since only the successes give rise to observers who can wonder about their existence, it would be a mistake to regard our planet as a randomly selected sample from all planets. Which one of the following best expresses the main conclusion of the above argument?
4. Although it is sometimes suggested that the congestion caused by the bunching of cars on motorways could be eased by increasing the speed limit to 150 km/hr, such an increase would not be a good thing. An estimated 35 per cent of drivers exceed the speed limit by 20 km/hr and would continue to do so if the limit were raised. Since bunching is caused by speeding drivers trying to pass those who observe the speed limit, raising the limit to 150 km/hr would result in the same amount of congestion, but at an increased speed. Moreover, a higher speed limit would encourage all drivers to drive faster, and thus would increase the existing danger from those who drive too close to the car infront. Which one of the following best expresses the main conclusion of the above argument?
5. Food producers are resisting pressure to reduce still further the levels of salt in food. Although it is proven that salt intake must be reduced by those with hypertension, there is no evidence that reducing salt intake prevents hypertension. So why should we all be deprived of the pleasures of salt in food? We certainly need to identify those with hypertension and give them advice on their salt intake, but why should everyone else be deprived of salt? Food producers are right to resist the pressure. Which one of the following best illustrates the principle underlying the argument above?
6. Sports are played either as a means of getting exercise or as a competition with an opponent. Some sports, such as football, involve a large amount of running and some people are more motivated to run when it is part of a game. Other sports, such as pool, do not involve much physical activity and so it is unlikely that they would be played for the exercise. Which one of the following conclusions is best supported by the passage above?
7. Concern about the effects of chemicals upon the environment has led to calls for more research. But we should not wait for further research before we ban some of the chemicals used by industry. If anyone has a good reason to think something is harmful, it should not be used until, or unless, the risk is found to be zero. We know enough about past mistakes to be forewarned. Much of the harm to wildlife and humans is long-term, and the disturbing results we see today reflect the chemical environment 40 years ago. Thousands more chemicals have been released into the environment since then. Which one of the following most closely matches the reasoning above?
8. Children are being encouraged to take up gardening through special events at shows and activities in schools. It is hoped that an interest in gardening, and particularly growing one's own food, will make children more interested in learning about their food and they will therefore be deterred from eating junk food. The initiative should be supported and spread to more schools as quickly as possible. Which one of the following, if true, would most weaken the above argument?
9. Although the Earth supports life, it has a mysterious carbon deficit. Compared with other bodies in the solar system the Earth has far less carbon than would be expected for a planet that supports life. Originally it was thought that in the inner region of the dust disc where the Earth formed, temperatures soared high enough for the carbon to boil away. However, observations of developing solar systems have now suggested that the temperature would not have been high enough. It is more likely that fire is to blame. Hot oxygen atoms would have readily combined with carbon, burning to produce carbon dioxide. There would have been fewer of these oxygen atoms further away from the Sun. Which one of the following, if true, would most strengthen the above argument?
10. Undercover police investigators sometimes commit 'crimes' in order to convince the 'real criminals' that they are on the same side as them. Some of these activities have victims, although in the main these are other criminals – rival gang members for example. In committing what are technically offences the officers are preventing many more serious crimes by helping to convict and imprison dangerous criminals who might otherwise remain at liberty. But that is not really the point. A breach of the law is a breach of the law, whoever commits it and for whatever reason. Preventing a crime does not make it right to commit another crime. Which one of the following is the general principle underlying the above argument?
11. Looking in his rearview mirror, Graham sensed that there was something wrong with the number plate of the car behind him. When the car overtook him and he saw its rear plate he realised that the front plate had been upside down.
12. A local museum wishes to exhibit a collection of butterflies which is mounted in nine narrow (only 0.2 m wide) display cases, each 1.5 m long. The museum wants to arrange four tables, each 2 m long and 1 m wide, in such a way that all the display cases can be placed around the edges. The room for the exhibition is 6 m by 6 m and there must be at least 1 m of clear floor space around the outside of the tables. Which one of the five arrangements shown would be satisfactory?
13. Alberto has decided to paint his dining room. Paint comes in 1 litre cans. The paint in one can will cover an area of approximately 24 square metres. The dining room is 4 m x 6 m x 3.5 m high. There is just one window which is in one of the long walls and is 1.5 m x 2 m. All of the walls, door and ceiling are to be painted with the same type of paint. Approximately 20% of the wall area to be painted is wood which will need a second coat of paint. What is the minimum number of cans of paint that Alberto should buy to have sufficient to complete the room?
14. A farmer wishes to fix fencing rails to posts which are already in place. The posts are shown in the diagram. The farmer has a supply of rails, each one 2.4 m long. One rail or part of a rail is to be fixed between each pair of posts. (He can cut the rails into smaller lengths.) What is the smallest number of rails that he could use?
15. Tom is having a celebration and needs to send out 50 invitation cards. The cards must be at least 6 cm wide and at least 8 cm high and Tom wants to put a photo on the card. Each type of card has a standard version and a deluxe version. The prices (per card) that have been quoted to Tom are shown in the table below. Tom wants to buy the cheapest type of card possible but is willing to pay for the deluxe version instead of the standard. What is the total extra that Tom would have to pay to buy the deluxe cards?
16. The table below shows the average mass of the cerebellum, which is a part of the brain, and total body mass, for a number of animal species. The cerebellum of a cat has an average mass of 5.3 g, while a cat's average body mass is 3.5 kg. For which of the species shown is the ratio of cerebellum to total body mass closest to that of the cat?
17. There are two services between Sandpoint and Genville: a fast hovercraft service which takes 50 minutes and a slow ferry which takes 1 hour 40 minutes. They both stop in port for 20 minutes at each end before starting the return journey. They start out from Sandpoint together at the same time each morning. For how long has the slow ferry been sailing before it meets the hovercraft coming back? (Answer to the nearest minute if necessary.)
18. Deanna keeps a record of the petrol she puts into her car and the current distance it has covered so she can estimate her fuel consumption. When she puts petrol in, sometimes the tank is filled completely and she marks 'FULL' beside the entry if this is so, otherwise the tank is only partly filled. Her data for the last month is as follows. Which one of the following is the best estimate of her fuel consumption?
19. Leroy cycles to work each morning. The first half of his journey is uphill and he can manage only a steady 5 kilometres per hour. The second half, however, is downhill and he covers this at 15 kilometres per hour. Which one of these graphs could show Leroy's journey?
20. When I made a hotel reservation online yesterday I was given an 8digit booking reference which contained no zeros. It did, however, consist of three 2digit odd numbers followed by the sum of these three numbers, and all eight digits were different. The first digit of the booking reference was 4. What was the last digit?
21. Which one of the following pairs of scholar/field of study is NOT correct?
22. Which one of the following public figures was NOT awarded the Nobel Peace Prize?
1 di 4 23. The diagram below shows an amino acid. Which option correctly identifies both the variable group (R group) and the acidic group?
24. In a prokaryote, transcription can occur in which of the following?
25. Which of the following are directly produced during photolysis of water?
26. The table shows some events of the normal eukaryotic cell cycle. Which row shows the correct sequence of events (left to right) as they occur during part of this cell cycle?
27. A double stranded DNA molecule is shown below:
This DNA molecule is allowed to replicate three times in a medium containing nonradioactive nucleotides . Which answer shows the correct percentages of original DNA and completely nonradioactive DNA? [Assume all radioactive nucleotides remain radioactive throughout, and all nonradioactive nucleotides remain nonradioactive throughout].Non rispondere
28. The genotype QqRr produces a certain phenotype. If two individuals with a genotype of QqRr reproduce, how many different possible phenotypes could be created, assuming all allele combinations are equally viable and the phenotypes are the result of complete dominance?
29. A normal sequence of triplets in a section of DNA is given by: ATCGAACGG
The same section of DNA has been changed by mutation, and is given by: ATCTTGCGG Some of the triplets below represent the tRNA triplets which code for amino acids. Key: Using the tRNA triplets, which amino acid sequence given below could be formed from the mutated DNA sequence?Non rispondere
30. Which of the following could be the outcome of evolution?
Speciation Achange in allele frequency Increased biodiversity Non rispondere 31. Where in a shoulder joint are osteocytes found?
32. The diagram shows how the pressure changes in the left atrium, left ventricle and the aorta during one heartbeat in a healthy human.
Which row shows the correct events during time period X?Non rispondere
33. The diagram shows a single sarcomere in a relaxed state. Which answer describes the changes when the sarcomere contracts?
34. Some local anaesthetics affect nervous impulse transmission by making it more difficult for voltagegated sodium channels to open. In a human patient treated with these anaesthetics which of the following statements would be true?
35. The changes in concentration of hormones in a healthy woman's blood were monitored during several menstrual cycles. During which stage of the menstrual cycle was the concentration of oestrogen falling, the concentration of luteinising hormone (LH) and folliclestimulating hormone (FSH) maximal and the progesterone concentration rising?
36. The following events occur during a reflex response to a person placing a hand on a hot object. Which of the following options places four of these events in the correct order (from left to right)?
Myosin binding sites on actin filaments uncovered. ADP and phosphate ion released from myosin head. Sodium voltagegated channels open. Myosin head detaches from binding site on actin. Calcium ions released by sarcoplasmic reticulum. Non rispondere 3, 5, 4, 2
1, 2, 4, 3
3, 1, 4, 2
5, 1, 2, 4
5, 2, 1, 4
None 37. The picture below shows a DNA microarray. Each spot (labelled 1–4) contains a different DNA probe. A sample of fluorescentlylabelled human DNA, with the sequence TGGTCAAGATTAT, is washed over the array. Which of the spots would show a positive signal because it fluoresces?
38. In the nerve cells of a person, one gene has two alleles, ‘A’ and ‘a’, present. For this person, which row correctly shows the alleles present in all three different situations given in the table?
39. Place the following structures in a human sperm cell in descending order of size (left to right):
1, 2, 3
1, 3, 2
2, 1, 3
3, 1, 2
2, 3, 1
None 40. Which one of the following is NOT a carbohydrate?
2 di 4 41. What is the correct formula of propanal?
42. Which two of the following oxides would NOT give acidic solutions in water?
43. Assume that the oxidation numbers are as shown below. Which compound formula given below is correct?
44. 0.75 g of a hydrocarbon compound contains 0.60 g of carbon. Which one of the following could be the molecular formula of the hydrocarbon compound?
45. The atomic number of aluminium is 13. Which electron configuration given below corresponds to the Al²⁺ ion in its ground state?
46. When propan1ol is burnt in excess oxygen the only products formed are carbon dioxide and water. In the balanced equation for this reaction what is the ratio of CO₂ : H₂O molecules formed?
47. 2,2 – dimethylpropane, C(CH3)4, is an isomer of pentane, CH3(CH2)3CH3. Pentane has a boiling point of 36 °C whilst the boiling point of 2,2 – dimethylpropane is 10 °C. Which statement below explains the difference in the boiling points for these two substances?
48. Potassium nitrate was found to have a solubility of 120 g in 100 g of water at 80 °C and 50 g in 100 g of water at 25 °C. 50 g of water was heated to 80 °C and solid potassium nitrate added until the solution was just saturated. The solution was then cooled to 25 °C when solid potassium nitrate separated out to leave a saturated solution. Using the information provided in this question, what is the minimum mass of water that must now be added to the mixture of the solution and the solid in order to make this solid potassium nitrate redissolve at 25 °C?
49. Pure water selfionises. This endothermic reaction is represented by the equation: N₂0(I) ⇌ H⁺(aq) + OH⁻ (aq). Which of the following statements is true for pure water between the temperatures of 0 °C and 100 °C?
The concentrations of H+ (aq) and OH– 1. (aq) are equal between 0 °C and 100 °C. An increase in temperature causes the pH to fall. An increase in temperature causes the electrical conductivity to decrease. Non rispondere 50. Which one of the following 0.01 M aqueous solutions has a pH > 7.0?
51. Atoms X and Y form an ionic compound with formula XY₂. Which option below could give the correct atomic numbers for X and Y?
52. In the reaction: C₃H₇Br + KOH → C₃H₇OH + KBr. 24.6 g of 1bromopropane reacts with excess potassium hydroxide to produce 8.00 g of propan1ol.
Mᵣ : C₃H₇Br = 123 Aᵣ : H = 1.0; C = 12.0; O = 16.0 What is the percentage yield of this reaction?Non rispondere
3 di 4 53. The variables x and y satisfy the following two equations:
54. Evaluate: (27² – 23²) + (14² – 6²)
55. Given that 2 log₁₀ (x) – 3 = log₁₀ (y) express y in terms of x.
56. The arithmetic mean of the three numbers a, b, c is 8. Find the arithmetic mean of the four numbers: a + 1, b + 2, c + 6, 3.
57. An aluminium block of mass 2.5 kg is supplied with 9000 J of thermal energy. This causes its temperature to rise by 4 K. Which expression gives the specific heat capacity of this aluminium, from this data? [Assume that the block remains solid throughout, and that no additional energy is exchanged between the block and the surroundings.]
58. The diagram shows a car of mass 1000 kg travelling at a constant speed of 30 m/s in the direction shown along a flat, level road which forms a circle of radius 50 m.
Which row in the table gives both the magnitude of the resultant force on the car and the direction of the acceleration of the car at the instant shown?Non rispondere
59. Two forces F of equal magnitude act on a beam. Which diagram shows a couple acting and states the magnitude of the torque (moment) of the couple about the pivot? [The pivot is at the centre of the beam]
60. Which one of the following equations is dimensionally consistent (has consistent units)?
[All the symbols have their usual meanings: v = velocity; F = force; m = mass; t = time; V = voltage; Q = charge; R₁, R₂, R₃, R₄ = resistance]Non rispondere
4 di 4