INTERACTIVE MULTIPLE CHOICE QUESTIONS Principles of Biology 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 drawings represent stages in division of an animal cell. Which of the following is the correct sequence of events? a b (a) b, d, a, c (b) b, d, c, a c (c) b, a, c, d (d) b, c, d, a Question 2 d Yes This the correct sequence No The cell constricts (a) before the cells separate (c) No The nucleus divides (d) before the cell starts to constrict (a) No The separation into two cells is the final stage Question 2 The drawing represents a typical leaf cell from a plant. What structure or structures are missing from the drawing? (a) cell wall (b) cytoplasm (c) nucleus (d) chloroplasts Question 3 No The cell wall is present cell wall No The cytoplasm is present cytoplasm Yes The nucleus was omitted from the drawing nucleus No The chloroplasts are present chloroplasts Question 3 After being exposed to temperatures ranging from 50-60ºC, most enzyme cannot function because … (a) their molecules have been broken down (b) their molecules have changed shape (c) their composition has been changed (d) they cannot separate from their substrate Question 4 No The molecules remain intact at these temperatures Yes The molecules have been denatured. That is, their shape has changed so that they can no longer bind to their substrate No The composition of the enzyme molecule is usually unaltered at these temperatures No They are unable to combine with their substrate Question 4 Which of these statements is correct? The enzyme amylase … (a) breaks down starch and protein (b) works best at 50ºC (c) breaks down starch only (d) breaks down cellulose Question 5 No Enzymes act on only one type of substrate No Most enzymes are denatured (inactivated) at this temperature Yes Amylase acts on starch, breaking it down to maltose No The enzyme which breaks down cellulose would be a cellulase Question 5 In biology, the term respiration means … (a) the act of breathing (b) the release of energy from food substances (c) releasing energy from carbohydrates by combing them with oxygen (d) A procedure used to revive a person who has stopped breathing Question 6 No The act of breathing is called ventilation. It is a method of obtaining oxygen for aerobic respiration Yes The release of energy from the breakdown of food substances, such as glucose, is called respiration Partly right But this definition applies only to aerobic respiration. Energy can also be released from food by anaerobic respiration for which oxygen is not needed. No Reviving a person who has stopped breathing is called resuscitation. In First Aid this is done by the ‘mouth to mouth’ method. An outdated method, depending on compression of the thorax was called (misleadingly) ‘artificial respiration’ Question 6 Which of the following is NOT reliable evidence of respiration in a land-dwelling organism (a) Output of carbon dioxide (b) Production of water vapour (c) Uptake of oxygen (d) Loss of dry mass Question 7 This is reliable evidence The equation for aerobic respiration C6H12O6 + 6O2 6CO2 + 6H2O shows that production of carbon dioxide is good evidence of respiration This is not reliable evidence Although the equation for aerobic respiration C6H12O6 + 6O2 6CO2 + 6H2O shows that water is a product of respiration it is not good evidence of respiration because non-living material can produce water vapour by evaporation alone This is reliable evidence The equation for aerobic respiration C6H12O6 + 6O2 6CO2 + 6H20 shows that uptake of oxygen is good evidence of respiration. Admittedly, anaerobic respiration does not consume oxygen but it seems unlikely that a land dwelling organism would be using anaerobic respiration exclusively This is reliable evidence Although the equation C6H12O6 + 6O2 6CO2 + 6H20 shows glucose as the respiration substrate, almost any tissues can be used for respiration so a loss in dry mass means respiration is occurring. It has to be dry mass to avoid the loss of mass associated with evaporation Question 7 In a green plant, when the rates of respiration and photosynthesis are equal the plant will be …. (a) taking in carbon dioxide (b) giving out oxygen (c) taking in carbon dioxide and giving out oxygen (d) giving out water vapour Question 8 No The carbon dioxide needed for photosynthesis will all come from respiration 6CO2 + 6H2O C6H12O6 + 6O2 C6H12O6 + 6O2 (photosynthesis) 6CO2 + 6H2O (respiration) No All the oxygen produced by photosynthesis will be used for respiration 6CO2 + 6H2O C6H12O6 + 6O2 C6H12O6 + 6O2 (photosynthesis) 6CO2 + 6H2O (respiration) No There will be no net uptake of carbon dioxide or output of oxygen. All the carbon dioxide needed for photosynthesis will come from respiration, and the oxygen produced by photosynthesis will be used in respiration 6CO2 + 6H2O C6H12O6 + 6O2 (photosynthesis) C6H12O6 + 6O2 6CO2 + 6H2O (respiration) Yes There will be no net uptake of carbon dioxide or output of oxygen. All the carbon dioxide needed for photosynthesis will come from respiration, and the oxygen produced by photosynthesis will be used in respiration. (See previous slide). However, the plant will be transpiring and there will be a loss of water vapour Question 8 Which of the structures in these palisade cells from a leaf is responsible for photosynthesis? (a) 1 (b) 2 (c) 3 (d) 4 Question 9 1 2 3 4 Yes This structure is a chloroplast and is the site of photosynthesis No This structure is the nucleus. It controls the activities in the cell but does not photosynthesize No This is the vacuole. It may store sugars produced in photosynthesis but it does not photosynthesize No This is the cytoplasm. Most of the chemical processes of the cell occur in the cytoplasm, but not photosynthesis Question 9 Which of the following mineral ions does a plant need for making proteins? (a) Phosphate ions (b) Potassium ions (c) Nitrate ions (d) Magnesium ions Question 10 No Phosphate ions are needed for making DNA and for many enzyme reactions, but do not form part of proteins No Potassium ions are needed for certain reactions in the plant cell, including those leading to root formation, but they do not form part of a protein molecule Yes Nitrate ions are combined with the carbohydrate molecules produced during photosynthesis, and form amino acids and proteins No Magnesium ions are needed for forming chlorophyll but not for forming proteins Question 10 Diffusion of oxygen in air takes place as a result of… (a) convection currents (b) air movements (c) random movement of molecules (d) changes in temperature Question 11 No Convection currents would move the air as a whole. It would not specifically affect any one gas in the air No Air movements would affect all atmospheric gases in the same way Yes Small random movements of oxygen molecules results in their moving, eventually, from a place where the molecules are more abundant to places where they are scarcer, until they are evenly distributed No Changes in temperature affect all the atmospheric gases. A rise in temperature may speed up diffusion but not specifically of oxygen Question 11 In osmosis, water will diffuse through a partially permeable membrane… (a) from water to a concentrated solution (b) from a concentrated to a dilute solution (c) from a dilute solution to a concentrated solution (d) from a dilute solution to a more dilute solution Yes No The water movement in osmosis is from the dilute solution to the concentrated solution Yes No In osmosis the diffusion of water between solutions is always from the more dilute solution to the less dilute (i.e. more concentrated) solution End of questions Back to start End show