1 透過科學探究提升分析思維 e nhancement of a nalytical t hinking through s cientific i...
TRANSCRIPT
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透過科學探究提升分析思維 Enhancement of Analytical Thinking thr
ough Scientific Investigations
Instructor: Ann S N Lau
Lesson 3
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Fermentation 發酵
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Fermentation
Make use of yeast metabolism
Conversion of carbohydrates into
carbon dioxide, alcohol
acid, water, energy
depending on the availability of oxygen
http://en.wikipedia.org/wiki/Yeast
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The life cycle of Yeast
6http://en.wikipedia.org/wiki/Image:Yeast_lifecycle.svg
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Availability of Oxygen
Aerobic respiration
Undergo respiration in the presence of oxygen
Anaerobic respiration
Undergo respiration in the absence of oxygen
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Aerobic respiration
In the presence of oxygen:
C6H12O6 (Sugar) + O2 Pyruvate
Pyruvate CO2 + Water + Energy (ATP)
Glycolysis + Pyruvate oxidation + Krebs cycle
Krebs cycle: a series of enzymatic reaction in living cells that make use of oxygen in cellular respiration
Aerobic respirationNucleus
Mitochondrion
Oxygen
Sugar
Pyruvate
PyruvateInside mitochondrion
CO2 + Water + Energy (ATP)
Yeast cell
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Anaerobic respiration
In the absence of oxygen:
C6H12O6 (Sugar) + O2 Pyruvate
Pyruvate CO2 + Ethanol
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The use of Fermentation in Daily Life
http://en.wikipedia.org/wiki/Image:Dry_yeast.jpg
www.bread.com.tw
http://en.wikipedia.org/wiki/Image:Slice_bread.jpghttp://en.wikipedia.org/wiki/Image:Pain_aux_noix.jpg
http://en.wikipedia.org/wiki/Image:Sourdoughbreadcrumb.jpg
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Beer
Water + Starch source (malted barley)
+ Yeast + flavoring
Carbon dioxide + Ethanol
Anaerobic respiration of yeast
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http://en.wikipedia.org/wiki/Image:Sjb_whiskey_malt.jpg
http://www.budweiser.com/
www.heinekenhongkong.com/
http://en.wikipedia.org/wiki/Image:Leffe_900px.jpg
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In biotechnology……
Yeast fermentation
Production of proteins, e.g. insulin, human growth hormone, etc.
Short-life cycle
Secrete into the culture medium OR
Stored inside the cellFrom Hong Kong Institute of Biotechnology Ltd.
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Think……
Design an experiment
to
investigate the effect of
yeast fermentation in bread dough
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Materials: flour and water, yeast, incubator
What are the factors necessary for yeast growth?
What are the products produced by yeast cells?
What parameters of bread dough you would like to measure with the effect of yeast metabolism?
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Try a different way to record your data!
Plot graph using the statistical data
Diameter of Bread Dough Treated by Different Conditions
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5
10
15
20
25
30
0 5 10 15 20 25 30 35
Time (min)
Dia
met
er (m
m)