6 – To Investigate the Conditions Necessary for Fermentation (LC 2027) (Leaving Cert Biology): Flashcards
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Practise the cards
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Products of fermentation by yeast
Products of fermentation by yeast
Ethanol and carbon dioxide
Why boil glucose solution for 5 minutes?
Why boil glucose solution for 5 minutes?
Removes dissolved gases, creates anaerobic conditions
Purpose of oil layer in fermentation
Purpose of oil layer in fermentation
Prevents oxygen entering, maintains anaerobic conditions
Function of airlock in fermentation
Function of airlock in fermentation
Allows to escape, prevents oxygen entering
Ideal temperature for yeast fermentation
Ideal temperature for yeast fermentation
30°C
Limewater result when present
Limewater result when present
Turns cloudy or milky
Result in control without yeast
Result in control without yeast
No bubbles form, limewater stays clear
Reagents for ethanol test
Reagents for ethanol test
Potassium iodide and sodium hypochlorite
Positive test result for ethanol
Positive test result for ethanol
Pale yellow crystals
Effect of temps above 50°C on yeast
Effect of temps above 50°C on yeast
Denatures yeast enzymes, stops fermentation
Four conditions needed for fermentation
Four conditions needed for fermentation
Glucose, yeast, warm temp (30°C), anaerobic conditions
Products of aerobic respiration in yeast
Products of aerobic respiration in yeast
Carbon dioxide and water (not ethanol)
Why anaerobic conditions essential
Why anaerobic conditions essential
With oxygen, aerobic respiration occurs instead