65 - which enzyme is the major control point for glycolysis in muscle under most conditions .
a- glucokinase
b- hexokinase
c- phosphofructokinase
d- pyruvate kinase
answer is c .
-------------------------------------------------------------------------
66 - ATP in fast twitch muscle fibres is supplied predominantly by which type of glycolysis
a- aerobic
b- anaerobic
answer is b . anaerobic glycolysis .
------------------------------------------------------------------------------
67 - the rate of ATP production by anaerobic glycolysis can be upto 100 times faster than that of oxidative phosphorylation .
the above statement is true .
-------------------------------------------------------------------------
68 - under which conditions is the complete oxidation of pyruvate mediated by citric acid cycle ?
a- aerobic
b- anaerobic
answer is a .
---------------------------------------------------------------------------------
69 - impaired substrate cycling may lead to a lack of nonshivering thermogenesis and result in cold sensitivity in obese individuals .
the above statement is true .
--------------------------------------------------------------------------------------
70 - which molecule acts as a signal amplifier when concentrations of ATP are low to increase the phosphofructokinase activity ?
a- ADP
b- ATP
c- AMP
d- NADH
answer is c . AMP .
-----------------------------------------------------------------------------------
71 - Ribulose 5 phosphate ( RU5P ) is converted to ribose 5 phosphate ( R5P ) by the enzyme ?
a- ribulose 5 phosphate dehydrogenase
b- ribose 5 phosphate dehydrogenase
c- RU5P ISOMERASE
d- R5P ISOMERASE
the answer is C .
-----------------------------------------------------------------------------------
72 - which aminoacid side chain forms the schiff base with the substrate in the aldolase reaction ?
a- arginine
b- serine
c- tyrosine
d- lysine
answer is d.
------------------------------------------------------------------------------------
73 - lactate formed in skeletal muscle cells during anaerobic glycolysis is carried back to the liver , where it is used to synthesize
a- glucose
b- fructose
c- fatty acids
d- amino acids
answer is a .
-----------------------------------------------------------------------------
74 - flouride ion inhibits glycolysis by inhibiting the action of which enzyme ?
answer - enolase
aldolase
----------------------------------------------------------------------
75 - what is the enzyme which catalyses the formation of glyceraldehyde 3 phosphate and dihydroxy acetone phosphate ?
a- aldolase
b- enolase
c- kinase
d- mutase
answer is a . aldolase .
TO READ COMPLETELY ABOUT GLYCOLYSIS CLICK HERE
-----------------------------------------------------------------------
Showing posts with label glucose-6-phosphate. Show all posts
Showing posts with label glucose-6-phosphate. Show all posts
Tuesday, January 8, 2008
8 - biochemistry mcqs - 54 to 64 - glycolysis
54- in glycolysis ?
ans- glucose is converted inot 2 molecules of pyruvate by the synthesis of two NADH and 2 ATP molecules and utilisation of 2ATP molecules too .
- i dont wanna give u choices in this question because it confuses u a lot , so stick to the above statement .
-------------------------------------
55 - the compound which reduces the affinity of pyruvate kinase for its substrate ?
a- phosphoenol pyruvate
b- pyruvate
c- NADH
d- ATP
answer is ATP .
The pyruvate kinase converts phosphoenol pyruvate to pyruvate and in this reaction ATP is synthesized .
-----------------------------------------------------------------------------
56 - in muscle , glycolytic flux is subject to regulation by substrate cycling .
the above statement is true .
-------------------------------------------------------------------
57 - a deficiency of type B aldolase , results in __________ intolerance , a self limiting genetic disease ?
a- fructose intolerance
b- glucose intolerance
c- galactose intolerance
d- ribose intolerance
the answer is a .
-----------------------------------------------------------------------------------
58 - the isomerisation of glucose-6-phosphate to fructose-6-phosphate is catalysed by which enzyme ?
a- hexokinase
b- glucokinase
c- phosphoglucose isomerase
d- phosphofructo kinase
answer is c . phosphoglucose isomerase.
------------------------------------------------------------------------------------------
59 - the glyceraldehyde 3 phosphate dehydrogenase reaction is exergonic and will therefore proceed in the forward direction ?
the above statement is false . the glyceraldehyde 3 phosphate dehydrogenase reaction is slightly endergonic , but is pulled forward by the subsequent reaction of phosphoglycerate kinase . phosphoglycerate kinase converts 1 , 3 bisphosphoglycerate to 3 phosphoglycerate .
--------------------------------------------------------------------------------------
60 - the rate of NADPH production is controlled by the rate of glucose-6-phosphate dehydrogenase reaction .
the above statement is true .
------------------------------------------------------------------------------------------
61 - the exclusion of water from the active site of hexokinase is responsible for preventing the hydrolysis of ATP from being the dominant reaction during catalysis .
the above statement is true .
----------------------------------------------------------------------------------------------------------------
62 - phosphoglycerate kinase catalyses a step in glycolysis , which results in the formation of ATP .
the above statement is true . the enzyme phosphoglycerate kinase catalyses the conversion of 1 , 3 bisphosphoglycerate to 3 phosphoglycerate to produce one ATP .
--------------------------------------------------------------------------------------------------------------
63 - The hexokinase has very low affinity for hexoses .
the statement is true .
---------------------------------------------------------
64 - in two steps mannose is converted to ______, to enter into the glycolytic pathway ?
a- fructose 6 phosphate
b- glucose 6 phosphate
c- fructose
d- glucose
answer is a .
TO READ COMPLETELY ABOUT GLYCOLYSIS CLICK HERE
------------------------------------------------------------------------
ans- glucose is converted inot 2 molecules of pyruvate by the synthesis of two NADH and 2 ATP molecules and utilisation of 2ATP molecules too .
- i dont wanna give u choices in this question because it confuses u a lot , so stick to the above statement .
-------------------------------------
55 - the compound which reduces the affinity of pyruvate kinase for its substrate ?
a- phosphoenol pyruvate
b- pyruvate
c- NADH
d- ATP
answer is ATP .
The pyruvate kinase converts phosphoenol pyruvate to pyruvate and in this reaction ATP is synthesized .
-----------------------------------------------------------------------------
56 - in muscle , glycolytic flux is subject to regulation by substrate cycling .
the above statement is true .
-------------------------------------------------------------------
57 - a deficiency of type B aldolase , results in __________ intolerance , a self limiting genetic disease ?
a- fructose intolerance
b- glucose intolerance
c- galactose intolerance
d- ribose intolerance
the answer is a .
-----------------------------------------------------------------------------------
58 - the isomerisation of glucose-6-phosphate to fructose-6-phosphate is catalysed by which enzyme ?
a- hexokinase
b- glucokinase
c- phosphoglucose isomerase
d- phosphofructo kinase
answer is c . phosphoglucose isomerase.
------------------------------------------------------------------------------------------
59 - the glyceraldehyde 3 phosphate dehydrogenase reaction is exergonic and will therefore proceed in the forward direction ?
the above statement is false . the glyceraldehyde 3 phosphate dehydrogenase reaction is slightly endergonic , but is pulled forward by the subsequent reaction of phosphoglycerate kinase . phosphoglycerate kinase converts 1 , 3 bisphosphoglycerate to 3 phosphoglycerate .
--------------------------------------------------------------------------------------
60 - the rate of NADPH production is controlled by the rate of glucose-6-phosphate dehydrogenase reaction .
the above statement is true .
------------------------------------------------------------------------------------------
61 - the exclusion of water from the active site of hexokinase is responsible for preventing the hydrolysis of ATP from being the dominant reaction during catalysis .
the above statement is true .
----------------------------------------------------------------------------------------------------------------
62 - phosphoglycerate kinase catalyses a step in glycolysis , which results in the formation of ATP .
the above statement is true . the enzyme phosphoglycerate kinase catalyses the conversion of 1 , 3 bisphosphoglycerate to 3 phosphoglycerate to produce one ATP .
--------------------------------------------------------------------------------------------------------------
63 - The hexokinase has very low affinity for hexoses .
the statement is true .
---------------------------------------------------------
64 - in two steps mannose is converted to ______, to enter into the glycolytic pathway ?
a- fructose 6 phosphate
b- glucose 6 phosphate
c- fructose
d- glucose
answer is a .
TO READ COMPLETELY ABOUT GLYCOLYSIS CLICK HERE
------------------------------------------------------------------------
Subscribe to:
Posts (Atom)
Subscribe Now: Feed
You are visitor number
