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Enzymes SQA Questions
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What you should know - ENZYMES A c________ is a substance which helps to s______ up a chemical reaction. It remains u________ at the end of the reaction. An enzyme is a p_______ which can act as a catalyst inside l_____ c_____ (b_______ c_________). Enzymes are important for the functioning of living cells because w_______ the aid of e________ the chemical reactions would take place too s______ to maintain life. Enzymes in a cell are used in ‘b________’ or ‘s_______’ atalyst peed nchanged rotein ivingells iological atalysts ithoutnzymes lowly reakdown ynthesis
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Breakdown is when an enzymes breaks down a l______ s________ molecule into s______ ones Synthesis is when an enzyme j_____ s______ substrate molecules t_________ to make a larger one P_______ and c__________ are examples of breakdown enzymes P______________ is a synthesis enzyme Enzymes are s________ – they will act only on o___ s__________ Enzymes are p________ Enzymes are affected by t__________ and __. arge ubstratemaller oinsmaller ogether epsinatalase hosphorylase pecific neubstrate roteins emperaturepH
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Enzymes revision 1 ells hemicaleactions ynthesis lucose tarch egradation atalase xygen
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ockey
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pecific changed emperature ptimum enatured epsin 7
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Effect of temperature on enzyme activity Enzyme activity increases rapidly Maximum enzyme activity- optimum temperature Enzyme is being denatured
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the temperature at which the enzyme has greatest activity the pH at which the enzyme has greatest activity
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1427 11 9 pepsin catalase
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8. Pepsin has a working range of ____ to _____. This means it ______________________ Pepsin has an optimum pH of ____. This means it has ________ ________ at pH 2 9. Catalase has a working range of ____ to _____. This means it ______________________ Catalase has an optimum pH of ____. This means it has ________ ________ at pH 9 pH1 pH4 is active between ph 1 and 4 pH2 maximum activity pH7 pH11 pH9 is active between ph 7 and 11 maximum activity
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catalase breakdown starch synthesis Fat Fatty acids + glycerol breakdown 12 3 4 56 phosphorylase 7 89 10 11 12 13 1415
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Enzymes revision 2 Speed up reactions Unchanged at the end of reaction Lower the energy needed for a reaction biological Chemical reactions Unchanged at end of reaction synthesisdegradation temperaturepH specific
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Control experiment A c______ experiment is set up to prove that the r______ are due to the f______ (v_________) under i___________ ontrol esultsactor ariable nvestigation Test tube containing 2ml amylase(5% concentration) + 5ml starch solution(10% concentration) Experiment carried out in a water bath at 37ºC Aim: An investigation is set up to prove that starch is digested by amylase enzyme to maltose sugar Draw and describe the control tube
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Test tube containing equal volume of water (2ml) equal volume of starch solution (5ml) equal concentration of starch solution ( 10% concentration) Same temperature ( 37ºC), same type of test tube etc The control p______ that starch digestion o___ occurs when a_______ is present roves nlymylase Q. In this investigation, what is the purpose of the control experiment
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1cm 3 glucose 1 phosphate (3%) 1cm 3 phosphorylase enzyme (1%) experiment carried out at room temperature (25ºC) Aim: An investigation is set up to prove that starch is synthesised by phosphorylase enzyme from glucose 1 phosphate Draw and describe two control tubes
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1cm 3 glucose 1 phosphate (3%) 1cm 3 distilled water experiment carried out at room temperature (25ºC) 1cm 3 phosphorylase enzyme (1%) 1cm 3 distilled water experiment carried out at room temperature (25ºC) AND
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Reliability R_________ an experiment i_________ r________ of r_______ (__,__.__) This shows that results are not u___________ or a ‘o___ o___’ Often an a________ is then calculated epeating ncreases eliabiltyesultsRRR nrepresentative neff verage
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Averages 1. Find the total number of bubbles Temperature (°C)1020304050 Bubbles (number/s)481440 Try this example … 4 + 8 + 14 + 4 + 0 = 30 2. Divide the total by the number of items There are 5 items in the table 30 5 = 6 Average = 6 bubbles/s 3.Don’t forget units in your answer To find the average number of bubbles … Temperature (°C)1020304050 Bubbles (number/s)02832 Click here for answer 15 ÷ 5 = 3 bubbles/s
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Percentages 1. Find the total number of bubbles Temperature (°C)1020304050 Bubbles (number/s)481640 What percentage of bubbles are produced at 30ºC? 4 + 8 + 16 + 4 + 0 1. Find the total = 32 2. Divide the number of bubbles at 20ºC by the total number 8 32 = 0.25 this is the decimal fraction 0.25 x 100 = 25% To find the percentage of bubbles at 20ºC … 3.Multiply the decimal fraction by 100 to get the percentage 25% of the bubbles are produced at 20ºC 16 32 = 0.5 x 100 = 50% 10ºC? 4 32 = 0.125 x 100 = 12.5%
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Ratios 10ºC:20ºC 4 bubbles:8 bubbles Temperature (°C)1020304050 Bubbles (number/s)481442 1. Write down the ratio of the numbers To find the simple whole number ratio of bubbles at 10 degrees compared to bubbles at 20 degrees … 2. Find a number that will divide into both numbers to give a whole number – in this case 2 4 bubbles 2:8 bubbles 2 =2 bubbles:4 bubbles 3. Repeat step 2 until you cannot divide again without getting a fraction 2 bubbles 2:4 bubbles 2 =1 bubble:2 bubbles
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Ratios 20ºC:30ºC 8 bubbles:14 bubbles Temperature (°C)1020304050 Bubbles (number/s)481442 1. Write down the ratio of the numbers To find the simple whole number ratio of bubbles at 20 degrees compared to bubbles at 30 degrees … 2. Find a number that will divide into both numbers to give a whole number – in this case 2 8 bubbles 2:14 bubbles 2 =4 bubbles:7 bubbles 3. You cannot divide any more without getting a fraction so … the simple whole number ratio is: 4 :7
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apple liver Equal mass of tissue Same temperature Equal concentration of hydrogen peroxide
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Same apparatus with dead tissue Improves reliability 35
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16 Optimum pH specific
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√ 30 45 55 - 60 specific
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