Enzymes
Enzymes are vital chemicals in all living things. They are proteins that speed
up, and control, the chemical reactions inside the cells. If enzymes do not function
properly, the cell or even the whole organism can die. This chapter will look at
enzymes, and also some deficiency diseases, where people are born with a lack of
a particular enzyme.
A)
Web site name: Florida State College Jacksonville
Web URL: http://web.fscj.edu/David.Byres/enzyme1.html
Read “Mechanisms of Enzyme Action”
1).
What are the two main roles of enzymes? ___________________________
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2).
What is a “substrate”? ___________________________________________
3).
In the first diagram (with sucrase), is the substrate broken apart into two
products, or are two substrates joined to make a single product?
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4).
What are two ways that the barrier of activation energy can be overcome?
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5).
If the temperature of an enzyme controlled reaction increased from 10oC to
30oC, the reaction rate will typically :
a) double
b) triple
c) quadruple
d) increase 9-fold
6).
What happens to most enzymes above 50oC ? ________________________
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7).
Which organisms have enzymes that can work efficiently at –2oC ?
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8).
What is the optimum pH for pepsin? _______________________________
9).
What is inhibition? _____________________________________________
10). Chemicals that are very similar to the true substrate are ________________
inhibitors.
11). Why are non-competitive inhibitors unaffected by substrate concentration?
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12). What is a “prosthetic group”? _____________________________________
13). Why does the stomach lining not get digested by pepsin? _______________
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14). What type of reaction is done by Lyases? ___________________________
15). How are the following enzymes used commercially?
a) Substilin : __________________________________________________
b) Glucose oxidase : ____________________________________________
B)
Web site name: Maricopa Community College
Web URL: http://www2.estrellamountain.edu/faculty/farabee/BIOBK/BioBookEnzym.html#Enzymes
Read “Enzymes: Organic Catalysts”
16). What is a “catalyst”? ____________________________________________
17). How do catalysts lower the activation energy? ________________________
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18). Carbonic anhydrase causes chemicals to react ________ times faster than
without the enzyme.
19). What is the “induced fit hypothesis”? _______________________________
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20). What are “thermolabile enzymes” ? ________________________________
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21). What is the optimum pH for the enzyme Arginase? ____________________
22). How does sulfanilamide kill bacteria? ______________________________
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23). Which of the four competitive inhibitors shown in the diagram is the most
similar in structure to succinate? __________________________________
24). What effect do the following inhibitors have ?
a) nerve gas : _________________________________________________
c) Penicillin : _________________________________________________
Some people are born with a lack of a particular enzyme. One example of a
“deficiency genetic disease” like this is called Tay-Sachs disease.
C)
Web site name: Disabled World
Web URL: http://www.disabled-world.com/disability/types/tay-sachs.php
Read “Tay-Sachs Disease”
25). In Tay-Sachs disease, which fatty substance builds up in nerves?
_______________________________________
26). Which enzyme has a “lack of sufficient activity” in Tay-Sachs disease?
_____________________________
27). What are the symptoms in children with this disease? _________________
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28). What are the symptoms for the rare form of Tay-Sachs disease (TSD) that
occurs in people in their twenties? _______________________________
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29). Which populations have a high risk of TSD?
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30). How can carriers of the disease be identified? ______________________
31). If both parents are carriers of TSD, what is the chance of their child being
born with TSD? _____%
32). Which chromosome carries the gene for TSD? ______________________
33). People who are carriers of TSD have a _____% chance of passing on the
active gene to their children.
D)
Web site name: Medicine Net
Web URL: http://www.medicinenet.com/g6pd_deficiency/article.htm
34). Which part of the body is mainly affected by this condition? ___________
35). What are three symptoms of hemolytic anemia? _____________________
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36). Which food can cause hemolytic anemia ? ___________________________
37). How many people worldwide suffer from this deficiency? ______________
38). Which disease does this G6PD deficiency protect people against?
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39). In which parts of the world is G6PD deficiency most common?
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40). Why is this deficiency more common in men than in women?
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E) Web site name: Science Daily
Web URL: http://www.sciencedaily.com/releases/2013/03/130308111312.htm
41). How soon could anti-aging drugs be on the market? __________________
42). Which diseases could this drug prevent? ______________________________
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43). What is the target enzyme? ___________________________
44). What two things can switch on this enzyme naturally?
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45). Where is resveratrol found in small quantities? ________________________
46). Why is this new drug unusual in the history of pharmaceuticals?
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47). Which disease are statin drugs used to prevent? ________________________
48). What possible problems or disadvantages could result if in future this new
drug is widely prescribed to prevent age related diseases?
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49). Would you personally like to “live to 150”? Explain why.
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