Total marks: 60 · Duration: 1 hour 15 minutes
Instructions to candidates
- This paper has 60 questions. Answer ALL questions.
- Each question is worth ONE mark.
- For each question there are four options, A, B, C and D. Choose the ONE you think is correct and record it on your answer sheet.
- You may use a silent, non-programmable electronic calculator.
- Where a question describes an organism, a process or a genetic cross in words, you may find it helpful to make a quick sketch.
Paper
Section A — Living Organisms in the Environment
1. Which of the following is a characteristic of ALL living organisms?
A) Movement from place to place
B) Excretion of waste products
C) Possession of a nervous system
D) Production of seeds
2. In the scientific name Homo sapiens, the word Homo is the name of the
A) kingdom
B) family
C) species
D) genus
3. Which feature places an organism in the plant kingdom?
A) Cells with walls made of chitin
B) Feeding by taking in other organisms
C) Cells with no nucleus
D) Cells with cellulose walls and chloroplasts
4. To estimate the number of crabs on a mangrove mud flat, 40 crabs are caught, marked and released. A week later, 50 crabs are caught, and 10 of them are marked. The estimated population is
A) 90
B) 2000
C) 200
D) 100
5. In the food chain grass → grasshopper → lizard → hawk, the lizard is a
A) producer
B) secondary consumer
C) primary consumer
D) tertiary consumer
6. The producers in an ecosystem contain 20 000 kJ of energy. About 10% is passed on at each step. The energy available to the primary consumers is about
A) 200 kJ
B) 20 000 kJ
C) 2000 kJ
D) 18 000 kJ
7. Which process removes carbon dioxide from the atmosphere?
A) Combustion
B) Decomposition
C) Photosynthesis
D) Respiration
8. Nitrogen-fixing bacteria in the root nodules of legumes convert
A) nitrites into nitrates
B) proteins into ammonia
C) nitrates into nitrogen gas
D) nitrogen gas into nitrogen compounds
9. Rhizobium bacteria live in the root nodules of bean plants. The bacteria receive sugars and the plant receives nitrogen compounds. This relationship is
A) parasitism
B) commensalism
C) predation
D) mutualism
10. A tick feeds on the blood of a cow. This relationship is
A) parasitism
B) mutualism
C) commensalism
D) competition
11. Which is a likely result of cutting down mangrove forests along a coastline?
A) More nursery grounds for young fish
B) More habitats for coastal birds
C) Increased coastal erosion
D) Less flooding inland
12. Fertiliser washes from farmland into a pond. Which happens FIRST?
A) Death of fish
B) Fall in oxygen concentration
C) Rapid growth of algae
D) Increase in decomposing bacteria
13. Which of these materials is biodegradable?
A) Aluminium
B) Polythene
C) Glass
D) Paper
14. In the growth curve of a population of yeast, the phase in which the birth rate equals the death rate is the
A) lag phase
B) decline phase
C) stationary phase
D) exponential (log) phase
15. Which is an ABIOTIC factor affecting the plants on a forest floor?
A) Attack by parasites
B) Light intensity
C) Competition from other plants
D) Grazing by herbivores
Section B — Life Processes and Disease
16. The organelle in which aerobic respiration takes place is the
A) chloroplast
B) nucleus
C) ribosome
D) mitochondrion
17. Which structure is found in plant cells but NOT in animal cells?
A) Cell wall
B) Nucleus
C) Cytoplasm
D) Cell membrane
18. A microscope has an eyepiece lens of ×10 and an objective lens of ×40. The total magnification is
A) ×4
B) ×50
C) ×30
D) ×400
19. Osmosis is the movement of
A) water molecules from a dilute solution to a more concentrated solution through a partially permeable membrane
B) water molecules from a concentrated solution to a dilute solution through a partially permeable membrane
C) any molecules from a region of high concentration to a region of low concentration
D) solute molecules from a concentrated solution to a dilute solution through a partially permeable membrane
20. A red blood cell is placed in distilled water. The cell will
A) become plasmolysed
B) stay the same size
C) swell and burst
D) shrink
21. A plant cell is placed in a concentrated salt solution. The cell becomes
A) turgid
B) unchanged
C) plasmolysed
D) burst
22. An enzyme from the human body is kept at 70 °C for 10 minutes. It no longer works because
A) it has been used up in the reaction
B) its active site has changed shape (it is denatured)
C) it has been digested by other enzymes
D) its molecules are moving too slowly
23. A food sample is heated with Benedict's solution and gives a brick-red precipitate. This shows that the food contains
A) a reducing sugar
B) protein
C) starch
D) fat
24. The raw materials for photosynthesis are
A) oxygen and glucose
B) glucose and water
C) carbon dioxide and oxygen
D) carbon dioxide and water
25. A plant whose leaves turn yellow because it cannot make enough chlorophyll is most likely to be short of
A) magnesium
B) calcium
C) iodine
D) iron
26. A lack of vitamin C in the diet causes
A) anaemia
B) rickets
C) goitre
D) scurvy
27. In humans, the digestion of protein begins in the
A) large intestine
B) oesophagus
C) stomach
D) mouth
28. The main function of the villi in the small intestine is to
A) increase the surface area for absorbing digested food
B) absorb most of the water from faeces
C) produce bile
D) churn the food
29. During strenuous exercise, anaerobic respiration in human muscle produces
A) lactic acid
B) glucose and oxygen
C) ethanol and carbon dioxide
D) carbon dioxide and water
30. In humans, gaseous exchange takes place in the
A) bronchi
B) trachea
C) diaphragm
D) alveoli
31. During inhalation (breathing in),
A) the diaphragm contracts and flattens and the volume of the chest increases
B) the diaphragm relaxes and domes upwards and the volume of the chest increases
C) the ribs move downwards and inwards
D) the pressure inside the lungs rises above atmospheric pressure
32. Carbon monoxide in cigarette smoke is harmful because it
A) widens the bronchioles
B) is the main cause of lung cancer
C) makes the alveoli produce more mucus
D) combines with haemoglobin, reducing the oxygen carried by the blood
33. The blood vessel that carries oxygenated blood from the lungs to the heart is the
A) aorta
B) vena cava
C) pulmonary vein
D) pulmonary artery
34. The valves in veins
A) prevent the backflow of blood
B) filter the blood
C) pump blood towards the heart
D) increase the blood pressure
35. Antibodies are produced by
A) platelets
B) phagocytes
C) red blood cells
D) lymphocytes
36. In a flowering plant, xylem vessels transport
A) water and mineral salts
B) hormones only
C) sucrose and amino acids
D) oxygen only
37. The rate of transpiration from a leafy shoot increases when the
A) stomata close
B) humidity of the air decreases
C) light intensity decreases
D) temperature decreases
38. In humans, urea is made in the
A) pancreas
B) bladder
C) liver
D) kidney
39. In the kidney, ultrafiltration of the blood takes place in the
A) collecting duct
B) ureter
C) loop of Henle
D) glomerulus and Bowman's capsule
40. In a reflex arc, the neurone that carries impulses from a receptor to the spinal cord is the
A) relay neurone
B) sensory neurone
C) motor neurone
D) effector
41. When a person walks from a dark room into bright sunlight, the pupils
A) dilate, because the circular muscles of the iris contract
B) constrict, because the circular muscles of the iris contract
C) dilate, because the radial muscles of the iris contract
D) stay the same size
42. The hormone that lowers the blood glucose concentration is
A) glucagon
B) insulin
C) adrenaline
D) thyroxine
43. Which disease is caused by a virus?
A) Ringworm
B) Malaria
C) HIV/AIDS
D) Tuberculosis
44. The Aedes aegypti mosquito transmits
A) malaria
B) dengue fever
C) tuberculosis
D) cholera
45. When the arm is bent at the elbow,
A) the triceps contracts and the biceps relaxes
B) both the biceps and the triceps relax
C) the biceps contracts and the triceps relaxes
D) both the biceps and the triceps contract
Section C — Continuity and Variation
46. Mitosis produces
A) four cells that are genetically identical
B) two cells that are genetically identical to the parent cell
C) four cells that are genetically different
D) two cells that are genetically different
47. A human body cell contains 46 chromosomes. The number of chromosomes in a human sperm cell is
A) 46
B) 92
C) 23
D) 22
48. In humans, meiosis takes place in the
A) testes and ovaries
B) bone marrow
C) skin
D) liver
49. In humans, fertilisation normally takes place in the
A) oviduct (Fallopian tube)
B) vagina
C) ovary
D) uterus
50. The main function of the placenta is to
A) produce sperm
B) allow substances to pass between the mother's blood and the fetus's blood without the two mixing
C) mix the mother's blood with the fetus's blood
D) store eggs until they are fertilised
51. Which method of birth control also protects against sexually transmitted infections?
A) Contraceptive pill
B) Intra-uterine device (IUD)
C) Vasectomy
D) Condom
52. A typical insect-pollinated flower has
A) brightly coloured petals and nectar
B) large amounts of light, smooth pollen
C) small green petals and no scent
D) feathery stigmas hanging outside the flower
53. Sugar cane plants grown from stem cuttings of one parent plant are
A) genetically identical to the parent
B) produced by meiosis
C) genetically different from the parent
D) produced by fertilisation
54. In pea plants, the allele for tall (T) is dominant to the allele for short (t). Two plants with genotype Tt are crossed. The percentage of the offspring expected to be tall is
A) 100%
B) 75%
C) 50%
D) 25%
55. An organism with the genotype Tt is described as
A) homozygous recessive
B) heterozygous
C) haploid
D) homozygous dominant
56. Sickle-cell anaemia is caused by
A) a gene mutation
B) a lack of vitamin B12
C) a lack of iron in the diet
D) a viral infection
57. A person who inherits the alleles Iᴬ and Iᴮ has blood group
A) A
B) B
C) O
D) AB
58. Red–green colour blindness is more common in males than in females because the allele is
A) carried on the Y chromosome
B) recessive and carried on the X chromosome, and males have only one X chromosome
C) dominant and carried on the X chromosome
D) carried on an autosome
59. Which is an example of discontinuous variation?
A) Height
B) Blood group
C) Body mass
D) Hand span
60. In the production of human insulin by genetic engineering, the human insulin gene is inserted into
A) red blood cells
B) sperm cells
C) bacteria
D) viruses
END OF TEST