Unit Two A Flashcards
1
Q
Gluconeogenesis mainly occurs where
A
Liver
2
Q
What are the two phases of glycolysis
A
Preparatory and payoff phase
3
Q
Aldolase creates what two triose phosphates
A
Dihydroxyacetone phosphate and glyceraldehyde 3 phosphate
4
Q
Fermentation regenerates what in glycolysis
A
NAD+ for further glycolysis under anaerobic conditions
5
Q
What regulates PFK1
A
ATP, fructose 2,6BP
6
Q
Kinase function
A
Transfer phosphate groups from ATP to various substrates
7
Q
Why is glycolysis heavily regulated
A
Proper use of nutrients, production of ATP only when needed
8
Q
What enzyme is used for rearrangement
A
Mutase
9
Q
What is the first step of pyruvate to phosphoenolpyruvate
A
Pyruvate carboxylase converts pyruvate and oxaloacetate
10
Q
Isomerization is
A
Aldose to ketose
11
Q
Ribose 5 phosphate is used for
A
DNA and RNA synthesis or synthesis of some coenzymes
12
Q
What occurs during step 8 of glycolysis
A
Migration of phosphate
13
Q
What step in glycolysis uses rearrangement
A
Step 8
14
Q
Animals cant produce glucose from what macromolecule
A
Fatty acids
15
Q
Step 6 of glycolysis pulls forward due to
A
Coupling to next reaction
16
Q
What is the substrate only used for step 6 of glycolysis
A
GAP
17
Q
What tissues use the pentose phosphate pathway
A
Liver and adipose tissue
18
Q
What occurs during rearrangement
A
Transfer of phosphoryl group from one atom to another
19
Q
CO2 produced in the first step of ethanol fermentation is responsible for
A
Carbonation in beer and dough rising
20
Q
Can mammals convert fatty acids to sugars
A
No
21
Q
Transketoalse uses what pathway
A
Pentose phosphate pathway
22
Q
When is glucose stored
A
When there’s plenty of excess energy
23
Q
Glycolysis generates
A
Energy via oxidation of glucose
24
Q
What is tautomerization
A
Effectively lowers the concentration of the reaction product
25
What are the main products of pentose phosphate pathway
NADPH and ribose 5 phosphate
26
Function of transketolase and transaldolase
Transfers 2 carbon glyceraldehyde from ketone to aldose
27
Pyruvate can be used as a precursor in
Biosynthesis
28
Reverse of Aldol cleavage
Aldol condensation
29
Rationale of step 10 for glycolysis
Substrate level phosphorylation to make ATP, net production of 2 ATP/glucose
30
What is the entry point of lactose into glycolysis
Lactose can be converted to galactose then enter through the galactose way or convert to glucose then glucose 6 phosphate
31
Pentose phosphate pathway generates
NADPH via oxidation of glucose
32
Rationale of step five of glycolysis
Allows glycolysis to proceed by one pathway
33
What is bound to ATP when used in first step of glycolysis
Mg2+
34
What is the entry point of glycogen into glycolysis
Glycogen can enter though glucose 1 phosphate or convert to glucose and convert to glucose 6 phosphate
35
Glucose 6 phosphate dehydrogenase deficiency has resistance to what
Malaria due to high oxidative stress in red blood cells
36
Fungal and bacterial aldolases employ what type of catalysis
Metal ion catalysis
37
What steps produce ATP
Step 7 and 10
38
Glucose 6 phosphate can be used in both
Glycogen synthesis and pentose phosphate pathway
39
In non oxidative phase of pentose phosphate pathway uses what enzymes
Transketolase and transaldolase
40
Do humans contain the enzyme pyruvate decarboxylase
No
41
Role of biotin (B7) in gluconeogenesis
Takes CO2 from HCO3- and places it on pyruvate to form oxaloacetate
42
What are the enzymes needed to go from pyruvate to ethanol
Pyruvate decarboxylase and alcohol dehydrogenase
43
The non oxidative phase of pentose phosphate pathway regenerates
Glucose 6 phosphate and ribose 5 phosphate
44
Pyruvate to phosphoenolpyruvate is how many steps
Two
45
What enzymes use TPP as coenzyme
Pyruvate decarboxylase, pyruvate dehydrogenase, alpha ketoglutarate dehydrogenase, transketolase
46
What is the transition molecule in glycolysis
Glucose 6 hosphate
47
Pyruvate tautomerization causes
Pyruvate to change form enol form to ketone form
48
The oxidative phase of pentose phosphate pathway uses what enzyme
G6P dehydrogenase to help produce NADPH
49
Rationale for increased glycolytic rate in tumor cells
Increases expression of hexokinase and GLUT 1 and 3, hypoxia increases expression of HIF-1alpha transcription factor leading to increase glycolytic enzymes
50
Why is step 7 of glycolysis reversible
Coupling to GAPDH reaction
51
What pulls step 9 of glycolysis forward
Product concentration kept low
52
The second step of pyruvate to PEP occurs where
Mitochondria or cytosol
53
What pulls step five of glycolysis forward
GAP concentration kept low
54
What is the middle intermediate of pyruvate to ethanol
Acetaldehyde
55
What is the solution to extract free energy from glucose anaerobically
Activation through phosphorylation then collect energy from the high energy metabolites
56
Gluconeogenesis occurs where
Liver
57
NADPH can regulate and inhibit what
Pentose phosphate pathway and will partition into glycolysis to transfer electrons
58
Where can lactate be converted into glucose
Liver
59
Glucose molecules are cleaved from glycogen and starch by
Glycogen phosphorylase
60
Step three of glycolysis favorable, unfavorable, reversible or irreversible
Favorable and irreversible
61
What is the entry point of galactose into glycolysis
UDP-galactose, UDP glucose then glucose 1 phosphate
62
What is the entry point of sucrose into glycolysis
Sucrose can convert to glucose and enter through glucose 6 phosphate or sucrose can convert to fructose and convert to fructose 6 phosphate
63
Pyruvate dehydrogenase uses what pathway
Acetyl CoA synthesis
64
NADPH is used for what in pentose phosphate pathway
Reductive biosynthesis of fatty acids and steroids and repair of oxidative damage
65
What is needed for aldose (glucose) to isomerize into a ketose (fructose)
Enediol intermediate
66
Is glycolysis the oxidation or reduction of glucose
Oxidation
67
Primary function of glutathione and glutathione reductase
Alleviate oxidative stress
68
The oxidative phase of pentose phosphate pathway generates what
NADPH and ribose 5 phosphate
69
What step in glycolysis uses dehydration
Step 9
70
Lactic acid fermentation by product is
NAD+
71
What regulates the first step of glycolysis
Substrate inhibition
72
What proteins can animals produce glucose from
Amino acids that can be converted to citric acid cycle intermediates or glycogenic amino acids
73
What is dehydrogenation
Oxidation of aldehyde with NAD+ gives NADH
74
In the second step of pyruvate to PEP becomes phosphorylated from
GTP and decarboxylation
75
TPP carries what
Acetaldehyde
76
When glucose molecules are cleaved from glycogen they create
Glucose 1-phosphate
77
What steps use ATP
Step 1 and 3
78
What is the second step of pyruvate to phosphoenolpyruvate
Phosphoenolpyruvate caroboxylase converts oxaloacetate to PEP
79
Are the reversible reactions in glycolysis and gluconeogenesis used by same or different pathways
Same pathways
80
What are the fates of pyruvate
Ethanol, acetyl CoA and lactate
81
What enzyme regulates FBPase1 in gluconeogensis
PFK
82
Glucose 6 phosphate to glucose in gluconeogensis uses what enzyme
Glucose 6 phosphatase
83
Why is 2 phosphoglycerate not a good enough phosphate donor
Two negative charges on it are fairly close and loss of phosphate from it would give a secondary alcohol with no further stabilization
84
Step five of glycolysis thermodynamically ????
Unfavorable, reversible
85
Alcohol dehydrogenase requires what coenzymes
Zn2+ and NAD+
86
Is the first or second step of ethanol fermentation produce NAD+
Second step
87
What cofactor is used with pyruvate carboxylase
Biotin
88
Rationale of step 9 of glycolysis
Generate a high energy phosphate compound
89
Glucose 6 phosphate dehydrogenase deficiency can be fatal during what
High oxidative stress
90
What is the entry point of mannose into glycolysis
Mannose can be converted into mannose 6 phosphate then fructose 6 phosphate
91
Why do liver and adipose tissue use pentose phosphate pathway
Requires more NADPH than Ribose 5 phosphate
92
Irreversible reactions use what type of enzymes
Regulatory
93
TPP derived from
Thiamine
94
Is the regulatory step the fastest or slowest step
Slowest
95
Glucose is stored as
Glycogen
96
Function of Mg2+ when attached to ATP
Shields negative charges on ATP
97
The first step of pyruvate to phosphoenolpyruvate needs to be transported where and by what
Mitochondria via malate
98
Sucrose is hydrolyzed into
Glucose and fructose
99
The loss of phosphate from PEP in step 10 creates an
Enol that tautomerizes into ketone
100
What parts of body only generates ATP from glucose
Brain, nervous system, red blood cells
101
What is the active site on GAP
Cysteine
102
What enzyme is need to go from fructose 1,6bp to fructose 6 phosphate in gluconeogensis
Fructose bisphosphatase 1
103
Step six of glycolysis is thermodynamically???
Unfavorable, reversible
104
What is the cori cycle
Metabolic cooperation between muscle and liver to convert lactate into glucose
105
What occurs during Aldol splitting or cleavage
6 carbon to two 3 carbon molecule
106
What drives step two of glycolysis forward
Product concentration kept low
107
Pyruvate kinase requires what for activity
Divalent metals such as Mg2+ or Mn2+
108
What enzyme is needed for lactic acid fermentation
Lactate dehydrogenase
109
What are the cofactors or coenzymes in glycolysis
Mg2+, Mn2+ NAD+ and ATP/ADP
110
Pyruvate decarboxylase used in what pathway
Ethanol fermentation
111
What steps in glycolysis uses isomerization
Step 2 and 5
112
Rationale of step 7 of glycolysis
Substrate level phosphorylation to make ATP
113
Ribose 5 phosphate is a biosynthetic precursor of what
Nucleotides
114
Site of glycolysis
Cytosol
115
Is NADPH and electron acceptor or donor
Donor
116
Pentose phosphate pathway is used for
Detoxification and the biosynthesis of lipids and nucleotides
117
Rationale for step three of glycolysis
Further activation of glucose, allows for 1 phosphate/3-carbon sugar after step four
118
Step 7 of glycolysis thermodynamically???
Favorable, reversible
119
Is glycolysis anabolic or catabolic
Catabolic
120
Rationale of step of glycolysis
Traps glucose inside cell and lowers intracellular glucose concentration to allow further uptake
121
Rationale of step six of glycolysis
Generation of high energy phosphate compound, incorporates inorganic phosphate
122
What step in glycolysis uses phosphorylation
Step 1,3,7, and 10
123
Step 9 glycolysis thermodynamically???
Unfavorable, reversible
124
Is lactic acid fermentation irreversible or reversible
Reversible
125
Biotin is what type of carrier
CO2 carrier
126
Lactose hydrolyzed into
Glucose and galactose
127
What step in glycolysis converts NAD+ to NADH
Step 6
128
What is the entry point of fructose into glycolysis
Fructose can become fructose 6 phosphate or go through liver and convert to fructose 1 phosphate and convert to DHAP or glyceraldehyde then convert to GAP
129
Step 10 of glycolysis is regulated by
ATP, divalent metals
130
What drives the reaction of step 10 toward
| ATP formation
Tautomerization
131
What is the product of ethanol fermentation
2 ethanol and 2 CO2
132
What is step 7 makes ATP
1,3-bisphosphoglycerate donates the phosphate group to aDP
133
What step in glycolysis uses Aldol splitting or cleavage
Step 4
134
Alpha ketoglutarate dehydrogenase uses what pathway
Citric acid cycle
135
Animal and plant aldolases employ what type of catalysis
Covalent catalysis
136
What is fermentation of glycolysis
Generation of energy (ATP) without consuming oxygen or NAD+
137
Is the first or second step in ethanol fermentation produce CO2
First
138
Glycolysis is needed for
Short term energy needs
139
Glycolysis occurs mainly where
Muscle and brain
140
What is a product of fatty acid degradation
Acetyl Co-A
141
Is glycolysis anaerobic or aerobic
Anaerobic
142
What are the four major pathways of glucose utilization
Storage, glycolysis, pentose phosphate pathway, synthesis of structural polysaccharides
143
The isomerization is catalyzed by what in step two of glycolysis
Activate site glutamate via general acid/base catalysis
144
Step two of glycolysis favorable, unfavorable, irreversible, reversible
Unfavorable and reversible
145
Lactate builds up in muscle then is transported to
Liver
146
What attacks the ATP in the first step of glycolysis
Nucleophilic oxygen at C6 of glucose
147
What step is the first committed step of glycolysis
Step 3
148
What occurs in step six of glycolysis
Oxidation of aldehyde with NAD+ gives NADH
149
What reactions in glycolysis must be bypassed in gluconeogenesis
Irreversible pathways
150
Step 10 of glycolysis thermodynamically ????
Favorable, irreversible
151
Enzyme for step one of glycolysis
Hexokinase in animals and glucokinase in prokaryotes
152
Rationale of step four of glycolysis
Cleavage of six carbon sugar into two three carbon sugars, high energy phosphate sugars are three carbon sugars
153
Is the reaction from pyruvate to ethanol reversible or irreversible
Irreversible
154
What is the committed or regulatory step in glycolysis
Fructose 6 phosphate to fructose 1,6-bisphosphate
155
Some of the oxidation free energy in glycolysis is captured by
The synthesis of ATP and NADH
156
Step one of glycolysis uses what for energy
ATP
157
Why do the irreversible pathways in glycolysis and gluconeogensis differ
Different enzymes, different regulators
158
What is most important role of lactic acid fermentation
Regenerate NAD+ for glycolysis
159
What pull the reaction of step four of glycolysis forward
GAP concentration kept low
160
Is step one favorable, non favorable, irreversible or non irreversible
Irreversible and favorable
161
What are the cofactors of pyruvate decarboxylase
Mg2+ and TPP
162
Animals can produce glucose from macromolecules
Sugars and proteins
163
Step four of glycolysis thermodynamically :???
Unfavorable, reversible
164
Step two of glycolysis rationale
C1 of fructose is easier to phosphorylate by PFK. Allows for symmetrical cleave by aldolase
165
What step uses dehydrogenation
Step 6
166
What happens to active site of GAP
Forms high energy thioester intermediate and is subject to inactivation by oxidative stress
167
What steps use Mg2+ or Mn2+
Step 1, 8 and 10
168
What steps are the substrate level phosphorylation steps
Step 7 and 10
169
What sugars can animals can produce glucose
Pyruvate, lactate and oxaloacetate (3 or 4C)
170
What are the irreversible steps in glycolysis
Step 1,3, and 10
