FEEDBACK TUTORIAL LETTER TEST 2 SECOND SEMESTER 2018 BASIC SCIENCE [BSC410S]

Transcription

1 FEEDBACK TUTORIAL LETTER TEST 2 SECOND SEMESTER 2018 BASIC SCIENCE [BSC410S] 1

2 FACULTY OF HEALTH AND APPLIED SCIENCES DEPARTMENT OF NATURAL AND APPLIED SCIENCES BSC PROGRAMME NAME ST. #:. QUALIFICATION(S): CENTRE:. (for DISTANCE students only) MODE OF STUDY: FM PM DM CLASS VENUE: FHAS Aud. Aud. 1 Mining Aud. COURSE NAME: COURSE CODE: BASIC SCIENCE BSC410S DATE: 05 OCTOBER 2018 DURATION: MARKS: 2 HOURS /90 BASIC SCIENCE TEST 2, SEMESTER 2 EXAMINER(S): Mr. V. INDONGO Mr. D. NANHAPO Mr. P. PAULUS INSTRUCTIONS: 1. Answer all the questions in this questions paper. 2. For Multiple Choice questions, CYCLE the correct answer with a blue/black INK pen. 3. No books, notes and other additional aids are allowed. 4. The Periodic Table is attached at the back of this paper. PERMISSIBLE MATERIALS Only a scientific calculator is allowed This paper consists of 12 pages including this cover page 1 P a g e

3 SECTION A: BIOLOGY [30] QUESTION 1 (20) Question Type: Multiple Choices. Each answer equals 2 mark. 1.1 Which of the following statements about ecology is INCORRECT? (2) A. Ecology is the study of the interactions between biotic and abiotic aspects of the environment. B. Ecologists may study populations and communities of organisms. C. Ecology is a discipline that is independent from natural selection and evolutionary history. D. Ecology spans increasingly comprehensive levels of organization, from individuals to ecosystems. 1.2 Indicate the correct order of the ecological hierarchy from the largest to the smallest? (2) A. Biosphere Ecosystem Community Population Organism B. Organism Population Community Ecosystem Biosphere C. Kingdom Phylum Class Order Genus Species D. Species Genus Order Class Phylum Kingdom 1.3 Which organisms are the most important to the functioning of the ecosystem? (2) A. Sun and Water B. Carnivores and Herbivores C. Producers and Decomposers D. Omnivores and Producers 1.4 Energy in the ecosystem is transferred from one trophic level to the next in a linear from. How much energy will be quaternary consumer get, considering the that the producer had J of energy. (2) A J B J C. 75 J D. 750 J 2 P a g e

4 1.5 Identify the types of ecological interactions are being illustrated by pictures I and II respectively? (2) I A. Competition and Predation B. Interspecific competition and Cooperation C. Intraspecific competition and Mutualism D. Intraspecific competition and Cooperation II 1.6 Which statement best define nutrition? (2) A. The consumption of food substances to get energy B. The consumption of a balance diet for growth and health C. The breakdown of polysaccharides by enzymes to release energy D. The transportation of energy to the central nervous system 1.7 One of the key benefit humans get from dietary fibers (cellulose) is that. (2) A. Dietary fibers provide humans with energy B. Dietary fibers (Cellulose) builds the cell walls of human cells C. They help to clean up and exercise the human digestive system D. They store energy need for the future by humans 1.8 Amino acids that are not synthesized in the body and must be obtained from the diet are called. (2) A. Good amino acids B. Essential amino acids C. Non-essential amino acids D. Conditional amino acids 3 P a g e

5 1.9 Goiter, the swelling of the neck is caused by a deficiency of which mineral. (2) A. Iron B. Iodine C. Potassium D. Sodium 1.10 Water makes up roughly 65% of our body weight. We take in water when we eat and drink. All the following statements are correct EXCEPT. (2) A. Water is important because chemical reactions in our cells take place in water. B. Waste products are passed out of our bodies in blood C. Our blood transports substances that are dissolved in water D. Water is in sweat that cools us down QUESTION 2 (10) Question Type: Structured questions 2.1 Use Figure 1 to answer Questions that follows. Figure 1. Simple food web Which type of consumer is the bird; herbivore, carnivore or omnivore? (1) Omnivore 4 P a g e

6 2.1.2 The organic and inorganic materials in all the organisms in the diagram will eventually return to the environment by the action of. (1) Decomposition Rabbits and grasshoppers are known as consumers. (1) Primary consumer 2.2. Briefly discuss two reasons why species get endangered or extinct? (2) Any correct two: - Loss of habitat - Overexploitation through excessive and illegal hunting - Pollution/ poison 2.3 Complete Table 1. (4) Table 1 Micronutrient Deficiency disease/signs Food source Vitamin A (i) Night blindness Milk, liver Vitamin C Bleeding gums (ii) Citrus fruits (iii) Iron Anaemia Liver Calcium (iv) Osteoporosis or Rickets Milk 2.4 State the disadvantage of taking in too much antibiotics (1) - Antibiotics kill the bacteria in intestine along with the pathogenic bacteria which leads to Vitamin K deficiency SECTION B: CHEMISTRY [30] QUESTION 3 (10) 3.1 What do you call a process which involves the input of energy or absorption of heat? (2) A. exothermic B. dissolving C. endothermic D. thermodynamic 3.2 Carbon dioxide is an example of a sample of matter classified as; (2) 5 P a g e

7 A. compound B. homogeneous mixture C. heterogeneous mixture D. element 3.3 In terms of composition, a dilute solution contains (2) A. a lot of solute in a given amount of solvent B. More solvent in a given amount of solute C. as much solute as the given amount of solvent D. None of the above 3.4 Fractional distillation involves two phase changes, which are; (2) A. evaporation and condensation B. evaporation and deposition C. evaporation and sublimation D. evaporation and melting 3.5 An appropriate physical method that can be used to separate two liquids with different boiling points is; (2) A. Chromatography B. Simple distillation C. Separating funnel D. Evaporation QUESTION 4 (20) 4.1 All matter can undergo physical and chemical changes. Briefly define the following terms: (2) a) Physical change: Change occurs when a substance alters its state (e.g. phase change), but does not change its chemical composition b) Chemical change: Change occurs when a substance is converted into a new or different substance that change in the composition of a substance 4.2 Classify the following as element, compound, homogeneous or heterogeneous mixture: (4) 6 P a g e

8 a) A piece of gold= element b) Calcium carbonate suspension= Heterogeneous mixture c) A potassium chloride solution= Homogeneous mixture d) Carbon monoxide= Compound 4.3 Distinguish between the following solutions: (2) a) A concentrated solution= A concentrated solution contains a lot of solute dissolved in a small amount of solvent. b) A diluted solution= A diluted solution contains small amount of solute dissolved in big amount of solvent. 4.4 Differentiate between solids and liquids in terms of their shapes. (2) Solids have a definite shape, whereas liquids have no definite shape, it follow the shape of the container. 4.5 Name the following phase changes and state whether the process is exothermic or endothermic: (2) a) Solid to gas = Sublimation & endothermic b) Gas to liquid= Condensation & exothermic 4.6 Is fermentation of sugar a physical or chemical change? Defend your answer. (2) Chemical change, because during this process a new substance is formed and the process is irreversible. 4.7 Table salt is chemically produced by reacting Sodium and Chlorine. Give a full chemical reaction equation as well as identify the reactants and product. (2) Reactants: Na and Cl; product: NaCl Chemical reaction: 2Na (s) + Cl2 (g) > 2NaCl (s) 4.8 Fill in the gaps (a h) in the table below. (4) Symbol Proton Neutron Electron Mass number Net charge (a) Fe (e) 24 (g) (b) Sn (c) 50 (d) S (f) (h) 2-7 P a g e

9 SECTION C: PHYSICS [30] QUESTION 5 (20) 5.1 An apple of mass 23 g fall from a tree at 5 m height. What is the potential energy of an apple? Hint: g = 9.8 m/s/s. (2) A J B J C J D J 5.2 A gas produced by burning fossil fuels and cause greenhouse effect is known as. (2) A. sulphur dioxide B. natural gas C. oxygen D. carbon dioxide 5.3 A type of energy source formed from the fossilized remains of pre-historic plant and animal material (2) A. fossil fuels B. biomass C. biofuels D. geothermal 5.4 Energy produced by the oceans as a result of movements of water flowing back and forth. (2) A. geothermal energy B. heat energy C. hydroelectric energy D. tidal energy 5.5 During the ascent phase of a rep of the bench press, the lifter exerts an average vertical force of 100 N against a barbell while the barbell moves 0.8 m upward. How much work did the lifter do to the barbell? (2) 8 P a g e

10 A. 0.8 J B. 800J C. 8000J D. 80 J 5.6 This symbol below is an example of a (2) A. cell B. resistor C. bulb D. variable resistor 5.7 If 8 coulombs of charge pass through a wire at a steady rate in 2 seconds, what is the current in this wire? (2) A A B. 4 A C. 16 A D. 8 A 5.8 A connects the components one after the other to form a single, closed circuit. (2) A. parallel circuit 9 P a g e

11 B. resistor C. series circuit D. cell 5.9 A measure of how much energy electrons receive is known as; (2) A. battery B. charge C. resistance D. voltage 5.10 The unit of charge Q is called; (2) A. coulomb B. ohm C. current D. electron QUESTION 6 (10) 6.1 Discuss how energy is produced from coal. (3) Coal is crushed into a fine dust Burn coal to heat water water turns into steam steam turns turbines turbines rotate generator to produce electricity. 7.4 Define the following terms: (i) Energy. (1) The ability or capacity to do work. (ii) power (1) The rate of transfer of energy. 7.3 A student with a mass of 20 kg stands at the top of a hill of height 0.4 km (Position A), as shown in the diagram below. Note: Answers should be in SI units 10 P a g e

12 a. What is the student s gravitational potential energy at the top of the hill? (3) Note: Gravitational acceleration (g) = 9.8 m.s -2 Gravitational potential energy (PE) = mgh = 20 kg x 9.8m.s -2 x (0.4 x 1000) m = kg.m 2.s -2 = Joules 6.4 State the difference between conventional and direct current. (2) Conventional current electrical current flows from positive to negative terminal Direct current - electrical current flows from negative to positive terminal END!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 11 P a g e

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