INTERACTIVE MULTIPLE CHOICE QUESTIONS Test 1 The answers are provided, but so also are explanations of why the alternatives are unsatisfactory © D.G. Mackean These multiple choice questions are similar to the ones set by the GCSE and IGCSE Examination Boards except that, in some cases, there may be more than one acceptable answer. For this reason, even if you select a correct answer at your first attempt, it is worth looking at all the alternatives (a) to see if there is a better answer and (b) to see why some of the alternatives are unacceptable. Question 1 Question 1 The process of aerobic respiration requires (a) A food source, oxygen, enzymes, a blood supply (b) A food source, carbon dioxide, enzymes (c) Oxygen, enzymes, sunlight (d) A food source, oxygen, enzymes Question 2 No Respiration occurs in all living cells including plants, bacteria and single celled organisms, none of which have a blood supply. No Carbon dioxide is a product of respiration No Sunlight is necessary for photosynthesis but not for respiration Correct answer Components of the food source are combined with oxygen, and energy is ‘released’*. Enzymes are catalysts which speed up these reactions * Most of the energy is used to drive other living processes though some it is released as heat Question 2 This organism is classified as an insect because it has (a) a segmented body (b) three pairs of walking legs (c) wings (d) jointed legs Question 3 No Insects do have segmented bodies but so do annelid worms such as the earthworm Yes This is the single characteristic of those listed that determines that the creature is an insect. However, you should bear in mind that if asked for a definition of an insect, all the characteristics listed should be included No Most insects do have wings but some are wingless e.g. fleas No Insects do have jointed legs but so do crustacea such as crabs and lobsters Jointed legs are a feature of the Arthropods, which include insects. Question 3 In a plant cell, which structure is responsible for controlling the entry or exit of substances? (a) The cell wall. (b) The cell membrane (c) The nucleus (d) The cytoplasm Question 4 No The cell wall is generally regarded as being freely permeable to water and dissolved substances. Its structure does prevent the passage of large molecules such as some proteins but this is not the same as exercising control This is the correct answer No The nucleus does control most of the activities in the cell but does not exert direct control over the entry and exit of substances. No The cytoplasm is responsible for constructing the cell membrane but does not exert direct control over the entry and exit of substances. Question 4 What will be the products of digestion of fish ? (a) Glucose and amino acids (b) Glucose, amino acids, fatty acids and glycerol, minerals and vitamins, (c) Glucose, glycerol and fatty acids (d) Glucose, amino acids, glycerol and fatty acids Question 5 No Fish contain fats as well as protein and carbohydrate No This is largely correct but vitamins and minerals are not digestion products. They are absorbed unchanged. If vitamins were broken down by digestion they would lose their properties No Fish contain proteins as well as carbohydrates and fats Yes The proteins are digested to amino acids. The carbohydrates are digested to glucose The fats are digested to glycerol and fatty acids Question 5 A male, homozygous dominant black mouse is mated with a homozygous recessive female brown mouse. The black genotype is BB, the brown genotype is bb. Would you expect the offspring to be (a) all brown (b) all black (c) 50% black and 50% brown (d) all intermediate in colour? Question 6 No All the male gametes will carry the dominant allele B. The female gametes will carry the recessive allele b. This means that the genotype of all the offspring will be Bb. There can be no brown mice (bb). Yes. All the male gametes will carry the dominant allele B. The female gametes will carry the recessive allele b. This means that the genotype of all the offspring will be Bb. Since the allele for black is dominant, all the offspring will be black No All the male gametes will carry the dominant allele B. The female gametes will carry the recessive allele b. This means that the genotype of all the offspring will be Bb. There can be no brown mice (bb). No If the alleles for black and brown fur were equally dominant (codominant), an intermediate colour might result but because only the black allele is dominant, this is not a possibility Question 6 Which of these organisms can be classed as producers in a food chain? (a) Earthworms (b) Mosses (c) Fungi (d) Trees Question 7 No Earthworms are near the bottom of a food chain but they are not producers. They are consumers, digesting and absorbing dead organic matter in the soil Yes Mosses are producers. Although they are simple plants they contain chlorophyll and produce their food by photosynthesis No Fungi are not producers. They digest and absorb organic matter in soil, dead wood or other decomposing matter Yes Trees are producers. The chlorophyll in their leaves enables them to produce food by photosynthesis Question 7 After blood has picked up oxygen in the lungs, what route does it take to deliver it to a muscle in the arm? (a) Pulmonary artery, left atrium, left ventricle, aorta, subclavian (to arm) artery (b) Pulmonary vein, left atrium, left ventricle, aorta, subclavian artery (c) Pulmonary vein, right atrium, right ventricle, aorta, subclavian artery (d) Pulmonary vein, right atrium, left ventricle, aorta, subclavian artery Question 8 No The vessels returning blood to the heart are the veins Yes This is the correct route. The oxygen will be used in respiration, perhaps to produce muscle contraction No The pulmonary vein returns blood to the left side of the heart No The right and left chambers of the heart are completely separate, Blood cannot cross from one side to the other. M Question 8 A is a weak solution of sugar in water. B is a strong solution of sugar in water. M is a selectively permeable membrane. After a period of time, the solution level will (a) rise in A and sink in B (b) rise in B and sink in A (c) remain the same (d) rise on both sides Question 9 A B No The water molecules in A can move freely. The sugar molecules in B attract a cluster of water molecules which therefore cannot move freely. Water molecules can pass through the selectively permeable membrane in both directions but there are more freely moving water molecules in A than in B Yes The water molecules in A can move freely. The sugar molecules in B attract a cluster of water molecules which cannot move freely. Water molecules can pass through the selectively permeable membrane in both directions but there are more freely moving water molecules in A than in B so more water will pass from A to B than in the other direction. The water level in A will therefore fall, and that in B will rise No This would happen if the membrane were freely permeable to water molecules and sugar molecules. The membrane, however, is selectively permeable You must be joking Question 9 Which of these statements is most accurate? In bright sunlight a green plant will be (a) photosynthesising only (b) respiring only (c) photosynthesising and respiring (d) taking in oxygen and giving out CO2 Question 10 No In bright sunlight the plant will certainly be photosynthesising, but this is not the only process going on No Living organisms are respiring all the time. A plant will be respiring in daylight and darkness, but in bright sunlight you would expect photosynthesis to be taking place as well Yes Respiration takes place all the time but in bright sunlight, photosynthesis will be going on as well. No Respiration uses oxygen and produces carbon dioxide. Photosynthesis uses carbon dioxide and produces oxygen. In bright sunlight, photosynthesis will be going on faster than respiration so there would be a net intake of carbon dioxide and a net output of oxygen Question 10 The force which carries water up a tree trunk is produced by (a) evaporation from the leaves (b) root pressure (c) osmosis (d) active transport Question 11 Yes Evaporation of water from the leaves (transpiration) produces a ‘water tension’ which ‘pulls’ water up through the xylem vessels in the trunk No Root pressure can certainly generate a force that ‘pushes’ water up through the vessels in the trunk but it is not sufficient to account for the rise which takes water to the top of a tree No Osmosis is responsible for creating root pressure but this is insufficient to drive water to the top of a tree No Active transport is something which happens in cells. It is usually concerned with the cell taking in specific substances. It cannot produce a mass flow of water. Question 11 A reflex action occurs when (a) a stimulus produces a response (b) a reaction to a stimulus cannot be consciously controlled (c) the nervous pathway involves only the spinal cord and spinal nerves (d) the reaction is very rapid Question 12 No There are many instances where a stimulus produces a response but they do not necessarily involve reflex actions. For example the stimulus of hunger produces the response to seek food. This is a voluntary response. Yes. For example, the ‘knee-jerk’ reflex cannot be consciously suppressed. No This is true in many cases but not all. The knee-jerk reflex is a spinal reflex but the reflex change of shape in the iris of the eye must have a nervous pathway in the brain. No Many reflex actions are rapid but others, such as reflex salivation in response to a sour taste, are comparatively slow. Also many voluntary actions are rapid. Some of the reactions in, for example, badminton are very rapid but they are not reflex actions Question 12 Pepsin, an enzyme in the stomach, will only work (a) in acid conditions (b) on carbohydrates (c) at 45ºC (d) on proteins Question 13 Yes The stomach secretes hydrochloric acid as well as pepsin. The pH is about 2 No An enzyme will act only on one specific substrate. Pepsin will not act on carbohydrates No At temperatures above 40ºC, most enzymes start to be denatured. That is, their molecular structure is altered and they no longer work. Pepsin will work best at body temperature, 36-37ºC Yes Pepsin acts only on proteins, breaking them down to smaller molecules called peptides Question 13 A sample of food is heated with Benedict’s reagent. If a red precipitate is formed it shows the presence of (a) sugar (b) starch (c) glucose (d) a reducing sugar Question 14 Yes The red precipitate does indicate that a sugar is present. It does not indicate which one; glucose, sucrose, fructose etc. No Starch should not give a red precipitate with Benedict’s reagent although it may produce a cloudy greenish suspension. This is because heating with an alkaline reagent (Benedict’s) starts to break down the starch to sugar Yes Glucose will certainly form a red precipitate when heated with Benedict’s reagent but so will several other sugars; fructose for example. In practice, the conclusion that glucose is present would be acceptable. Yes This is the best answer. A ‘reducing sugar’ is one which can ‘reduce’ the copper sulphate in Benedict’s reagent to copper (1) oxide (the red precipitate). Glucose, fructose, maltose and lactose are all reducing sugars Sucrose is not a reducing sugar and will not produce a red precipitate with Benedict’s reagent. Question 14 The human population grows if (a) the death rate exceeds the birth rate (b) the birth rate and death rate increase (c) people live longer (d) the birth rate exceeds the death rate Question 15 No If more people are dying than are being born, the population will diminish No If birth rate and death rate both increase, the population would remain stable but the age structure of the population would change No People living longer could increase the population size but unless the trend persisted it is unlikely to sustain a continuing increase in population Yes This is the principal cause of the growth of a population Question 15 g d e f The drawings represent stages in cell division in an animal cell, but in the wrong sequence. Which of the following is the correct sequence? a b c (a) b, e, d, a, c, f, g (b) b, d, e, a, c, f, g (c) b, e, d, a, c, g, f (d) b, e, a, d, c, g, f Question 16 No Cell constriction (g) occurs before the cells become separated (f) No The nucleus divides (e) before the cell starts to constrict (d) Yes This is the correct sequence No The cell constricts (d) before the cells become separate (a) Question 16 The female sex hormone is produced in (a) the uterus (b) the ovaries (c) the pituitary gland (d) the liver Question 17 No The uterus does not produce oestrogen Yes Oestrogen is produced in the ovaries No The pituitary gland releases two hormones. FSH and LH which affect the ovaries’ production of hormones but it does not produce oestrogen No* The liver processes oestrogen prior to its excretion but it does not produce it. * In fact the liver does produce small quantities of oestrogen but these are insignificant compared with oestrogen produced by the ovaries Question 17 Which of the following are excretory organs? (a) The liver (b) The kidneys (c) The sweat glands (d) The alimentary canal Question 18 No The liver produces bile. The green bile pigments are breakdown products of haemoglobin so they are excretory products. But the production of bile is a response to the presence of food in the duodenum and bile is not specifically formed to dispose of the bile pigments. So their excretion is incidental and the liver cannot be regarded as an excretory organ though it does process some excretory products which are excreted elsewhere Yes The kidneys are the excretory organs in the body. They excrete excess water, excess salt, urea and uric acid and the breakdown products of hormones and other unwanted products. No Sweat does contain sodium chloride and urea which can be regarded as excretory products. However, the sweat glands come into action in response to a rise in body temperature. The loss of salt and urea is quite incidental to the sweat glands’ function in temperature control. Therefore the sweat glands cannot be regarded as excretory organs. No The contents of the alimentary canal have never been part of the body, so defecation is not excretion. The bile pigments are excretory products from the liver but their excretion is incidental to the main function of the alimentary canal Question 18 Sexual reproduction occurs when (a) a new organism is formed (b) male and female gametes are produced (c) mating takes place (d) male and female gametes meet and fuse together Question 19 No A new organism could be the outcome of sexual reproduction but asexual reproduction also produces new organisms No The production of male and female gametes is an essential step in sexual reproduction but does not itself constitute sexual reproduction No In certain animals, mating may be a part of sexual reproduction but sexual reproduction takes place in plants and a great many other organisms where mating does not occur Yes The fusion of male and female gametes is the defining moment in sexual reproduction Question 19 The evidence and arguments for evolution by Natural Selection are (not in logical order)… (a) These variants live longer and have more offspring, (b) Organisms in a species tend to vary, (c) Some variants are better adapted to the environment than others, (d) Therefore there is a struggle for survival, (e) Organisms have more offspring than can possibly survive, (f) If the variations are heritable, the variants will eventually predominate,. Which of the following represents a logical sequence? (1) b, d, c, a, e, f (3) e, d, b, c, a, f (2) b, a, c, d, e, f (4) e, b, d, c, a, f Question 20 No The fact that organisms vary (b) does not necessitate a struggle for survival (d) The fact that organisms have more offspring than can survive (e) needs to come at an earlier stage in the argument No Because organisms vary (b) does not necessarily mean that they live longer (a). It is only the better adapted variants (c) which live longer (a) The tendency to have more offspring than can survive (e) must come at an early stage in the argument Yes This is the most logical sequence Not quite This is a reasonable sequence although the struggle for survival (d) is not necessarily a consequence of variation (b) Question 20 The DNA molecule consists of a strand of (a) the bases, adenine, guanine, thymine and cytosine (b) deoxyribose and phosphate (e) protein molecules (f) nucleotides No These organic bases are present in the DNA molecule but are only part of it No Deoxyribose and phosphate form the ‘backbone’ of the molecule but do not constitute it No Protein is present in the chromosomes but not in the DNA Yes. DNA is made up of a chain of nucleotides PO4 PO4 adenine deoxyribose A nucleotide bases PO4 PO4 PO4 Part of a DNA molecule End of questions Back to start End show