Exam II Flashcards
(201 cards)
1
Q
Monosaccharides:
A
Simple reducing sugars
2
Q
Disaccharides:
A
2 subunits (monosacchs) linked by glycosidic bonds. Monomers can be same/different sugars.
3
Q
Oligosaccharide subunits:
A
3-10
4
Q
Polysaccharide subunits:
A
> 10-100s, often indigestible
5
Q
Sugars contain either a/an ____ group or they contain a/an ____ group.
A
Aldehyde (carbonyl C on end)
Ketone (carbonyl C internal)
6
Q
Sugars are named by number of ____.
A
Carbons
7
Q
Disaccharides are created via monomer ____ synthesis.
A
Dehydration
8
Q
Glucose + Fructose=
A
Sucrose (most common)
9
Q
Glucose + Galactose =
A
Lactose
10
Q
Glucose + Glucose =
A
Maltose
11
Q
D sugar is identified by:
A
OH on bottom, chiral center points R
12
Q
L sugar is identified by:
A
OH on bottom, chiral center points L
13
Q
3 most common generic sugar names:
A
Glyceraldehyde (triose)
Ribose (pentose)
Glucose (hexose)
14
Q
Generic sugar names for 3, 4, 5, 6, 7, 9 Cs:
A
3-glyceraldehye 4-erythrose 5-ribose 6-glucose 7-sedoheptulose 9-neuraminic acid
15
Q
Isomers:
A
Same chemical formula but structurally different
16
Q
Structural isomer examples:
A
Fructose, glucose, mannose, galactose
17
Q
Epimers:
A
Carbohydrate isomers that differ in configuration around 1 specific C
18
Q
Stereoisomer examples:
C4, C2
A
Glucose and galactose- C4
Glucose and mannose- C2
19
Q
Enantiomers:
A
Mirror images (chiral)
20
Q
L and D sugars are considered:
A
Enantiomers
21
Q
For many enantiomer structures, ____ biologically active.
A
1 of 2
22
Q
Anomeric carbon:
A
Stereocenter formed with formation of 2 new diasteriomers
23
Q
Alpha-anomeric carbon points ____.
A
Down
24
Q
Beta-anomeric carbon points ____.
A
Up
25
Alpha and beta anomeric carbons ____ mirror images.
Aren’t
26
Reducing sugar determined by the state of the oxygen in the ____ group.
Aldehyde
27
If ____ group of an anomeric C of the cyclic sugar isn’t linked to another compound by glycosidic bond, the ring opens and closes.
Hydroxyl
28
Non-carbohydrate structures where glycosidic bonding is possible are: (5)
Purine, pyrimidine, aromatic rings, proteins, and lipids.
29
N-glycosidic links possible with ____ group.
NH2
30
O-glycosidic links possible with ____ group.
OH
31
Carbohydrate digestion is catalyzed by ____.
Glycoside hydrolases (glycosidases)
32
Enzyme for poly and oligosaccharides:
Endoglycosidase
33
Enzyme for tri and disaccharides:
Disaccharidase
34
Salivary alpha amylase acts briefly on ____ and ____ hydrolizing alpha 1-4 bonds.
Starch and glycogen
35
Dextrin is composed of:
Mixed short, branched and unbranched oligosaccharides
36
____ halts salivary alpha amylase in the stomach.
High acid
37
Small intestines further breaks down starch via:
Pancreatic alpha amylase
38
Monosaccharide absorption absorption occurs in ____ and ____.
Duodenum and upper jejunum
39
SGLT-1 transport protein transports ____ and ____ into mucosal cells.
Galactose and glucose
40
SGLT-1 is sodium ____.
Dependent
41
Glut-5 transport protein transports ____ into mucosal cells.
Fructose
42
Glut-5 transport is sodium ____.
Independent
43
Glut-2 transport protein transports galactose, glucose, and fructose from intestinal mucosal cell into the ____.
Portal circulation
44
Osmotic diarrhea is the result in a defect in a specific _____ enzyme.
Disaccharidase
45
Hypolactasia is apparent in ____ Caucasian adult population and ____ in African and Asian populations.
75% and 90%
46
Sucrase-isomaltase complex deficiency is passed genetically as
An autosomal recessive
47
Diagnosis of digestive enzyme deficiency is done by oral testing which does what?
Hydrogen test which identifies increased acetone in breath; increased ketones in blood and increased blood glucose.
48
In glycolysis pathways, the product serves as the ____ of the next reaction.
Substrate
49
In glycolysis, catabolic pathways are typically oxidative, coenzymes such as ____ are necessary.
NAD+
50
ATP consumption in glycolysis capable via ____, ____, and ____.
Glucokinase, hexokinase, and PFK
51
Oxidative decarboxylation part of glycolysis converts ____ to ____.
Pyruvate
| Acetyl CoA
52
In glycolysis, ATP produced with ____ and ____ enzymes.
PGK
| PK
53
In glycolysis, phase I ATP:
2 loss
54
In glycolysis, phase 2 ATP:
2 net gain
55
Glycolysis regulatory signals include:
Intracellular communication, intercellular communication, 2nd messenger systems, andenylyl cyclase
56
Intracellular communication for glycolysis regulation responds ____.
Rapidly
57
Intercellular communication for glycolysis regulation responds ____.
Slow
58
Glycolysis intracellular communication regulates:
Availability of substrates, product inhibition, alterations in levels of allosteric activators/inhibitors.
59
Glycolysis intercellular communication regulates:
Chemical signaling via blood borne hormones or neurotransmitters
60
In glycolysis, 2nd messenger systems:
Intervene between original messenger and ultimate effect on cell
61
In glycolysis, 2 types of 2nd messenger systems are:
Calcium/phosphatidylinositol and adenylyl cyclase systems
62
In glycolysis, adenylyl cyclase is:
Membrane bound enzyme that converts ATP to cAMP
63
Transport of glucose into cells for glycolysis ____ diffuse directly into cells.
Cannot
64
Transport of glucose into cells for glycolysis is ____ independent facilitated diffusion transport.
Na+
65
Na+ independent facilitated diffusion transport is mediated by which transports in cell membranes?
GLUT1-GLUT14
66
In glycolysis Na+ independent diffusion is either open for ____ or open to ____.
Extracellular glucose
| Transport glucose
67
Na+ independent facilitated diffusion transport requires ____ energy.
No
68
GLUT1:
RBCs BBB, glucose uptake
69
GLUT2:
Liver kidneys, transport glucose to and from
70
GLUT3:
Neurons, glucose uptake from blood
71
GLUT4:
Adipose skeletal muscle (increased with insulin), glucose uptake from blood
72
GLUT5:
Small intestines testes, fructose
73
Transport of glucose into cells is either ____ or ____.
Na+ independent facilitated diffusion transport
| ATP dependent Na+ monosaccharide co-transport system
74
ATP dependent Na+ monosaccharide cotransport system uses Na+ dependent ____ transporters to use to move.
Glucose
75
Na+ dependent glucose transporters use energy to move ____ and ____.
Against gradient
| Active transport
76
In glycolysis, anaerobic energy yield:
2 ATP/ 1 glucose converted to 2 lactate
77
In glycolysis, aerobic energy yield:
2 ATP/ 1 glucose
| 2NADH/ 1 glucose, mostly oxidized by ETC, 3 ATP/ NADH
78
2 hormones in glycolysis:
Insulin and glucagon
79
In glycolysis, insulin:
Activation of many enzymes, high glucose levels
80
In glycolysis, glucagon:
Adenylyl cyclase (ATP->cAMP), low glucose levels
81
Reactions unique to gluconeogenesis:
Carboxylation of pyruvate, transport of oxaloacetate to the cytosol, decarboxylation of cystosolic oxaloacetate, dephosphorylation of F 1,6-BP, Dephosphorylation of G6-P
82
In GNG, pyruvate 1st carboxylated by ____ to OAA
Pyruvate
83
In GNG, OAA converted to PEP via ____.
PEP-carboxykinase
84
in GNG, pyruvate carboxylase requires ____ coenzyme which covalently bonds to e amino group of lysine residue in enzyme.
Biotin
85
In GNG, hydrolysis of ATP drives formation of ____.
Enzyme-biotin-CO2 intermediate
86
OAA is formed in ____ of liver and kidney cells.
Mitochondria
87
Allosteric regulation of pyruvate carboxylase via ____.
Acetyl CoA
88
In GNG, increased levels of ____ in mitochondria, increased ____ of OAA is required.
Acetyl CoA
| Synthesis
89
During fasting, ____ synthesizes glucose via GNG in liver and kidney.
OAA
90
In GNG, with decreased levels of ____, pyruvate carboxylate is ____ and pyruvate is oxidized.
Acetyl CoA
| Inactive
91
In GNG, pyruvate is oxidized via ____ complex producing acetyl CoA for TCA oxidate.
Pyruvate dehydrogenase
92
OAA is converted to ____ for GNG to continue.
PEP
93
OAA cannot fit into mitochondrial membrane until ____
Malate dehydrogenase converts it to malate
94
Malate reoxidized to OAA via ____ as NAD+ reduces.
Cytosolic malate dehydrogenase
95
In GNG, ____ is decarboxylated and phosphorylated to PEP in cytosol via PEP CK reaction.
OAA
96
In GNG, hydrolysis of ____ leads to production of PEP in cytosol.
GTP
97
Is pyruvate carboxylate and PEP CK favorable or unfavorable pathway from pyruvate to PEP?
Favorable
98
Dephosphorylation of F 1,6-BP via:
Hydrolysis (F 1,6-BP-tase
99
Dephosphorylation of F 1,6-BP favorable or unfavorable pathway for formation of F6P
Favorable
100
F 1,6-BP-tase inhibited with elevated levels of:
AMP
101
____ levels of ATP and ____ concentrations of AMPT stimulate GNG.
High, low
102
Dephosphorylation of G6P via:
Hydrolysis (G6P-tase)
103
G6P-tase bypasses ____ hexokinase reaction and provides ____ pathway for formation of free glucose.
Irreversible
| Favorable
104
G6P ____ transports G6P across ER membrane.
Translocase
105
Biotin aids in the transfer of ____ groups.
CO2
106
Biotin’s main hormone regulation:
Glucagon
107
Glucagon comes from ____ cells of pancreatic islets.
Alpha
108
Glucagon ____ level of F 1,6-BP-tase and inhibit PFK-1 favoring GNG.
Decrease
109
Glucagon binds its ____ protein-coupled receptor.
G
110
____level of cAMP levels and cAMP dependent prokinase allow glucagon binding.
Increased
111
Glucose increases ____ of gene for PEP-CK-ase, increases ____ as ____ increases during fasting.
Transcription
Enzyme
Substrate
112
PFK-1: ____ regulatory enzyme in glycolysis
Irreversible
113
PFK-1: converts ____
F6P-> F 1,6-BP
114
PFK-2: acts on ____ but not in glycolytic pathway.
F6P
115
PFK: makes F 2,6-BP which further activates ____ stimulating glycolysis.
PFK-1
116
Pyruvate must be transported into ____ before it can enter TCA cycle.
Mitochondria
117
In TCA, pyruvate is converted to acetyl CoA via:
Pyruvate dehydrogenase complex-multi-enzyme
118
Pyruvate dehydrogenase complex not part of the TCA cycle but major source of ____.
Acetyl CoA
119
Citrate is synthesized from ____ and ____.
Acetyl CoA
| OAA
120
Citrate formation is catalyzed via ____.
Citrate synthase (Acetyl CoA and OAA condensed)
121
Aldol condensation has ____ directed at citrate synthesis.
Equilibrium
122
Citrate synthase is/is not an allosteric enzyme.
Is not
123
Citrate synthase is inhibited via ____.
Citrate (product)
124
Citrate synthase regulates ____ availability.
Substrate
125
Binding of OAA causes ____ in enzyme, making binding site for acetyl CoA.
Change
126
Citrate inhibits ____, the rate-limiting enzyme of glycolysis.
PFK
127
Citrate ____ acetyl CoA carboxylase.
Activates
128
Citrate isomerized via ____.
Aconitase
129
____ inhibits aconitase, increases citrate.
Fluorocitrate
130
In TCA, isocitrate dehydrogenase catalyzes ____ oxidative decarboxylation isocitrase.
Irreversible
131
Oxidation and decarboxylation of isocitrate yields:
1st NADH produced, 1st release of CO2
132
Isocitrate dehydrogenase allosterically actived by ____ and ____.
ADP
| Ca
133
Isocitrate dehydrogenase is inhibited by ____ and ____.
ATP
| NADH (increased with increased energy store)
134
Alpha-ketoglutarate dehydrogenase complex ____ alpha-ketoglutarate to succinyl CoA.
Catalyzes
135
Oxidative decarboxylation of alpha-ketoglutarate releases:
2nd CO2 and produces 2nd NADH
136
The following coenzymes are required for oxidative decarboxylation of alpha-ketoglutarate:
Thiamine pyrophosphate, lipoic aic, FAD, NAD+, CoA
137
Alpha-ketoglutarate dehydrogenase complex is inhibited by its products:
NADH
| Succinyl CoA
138
Alpha-ketoglutarate dehydrogenase complex activated by:
Ca
139
Alpha-ketoglutarate dehydrogenase complex is/is not regulated by dephosphorylation and phosphorylation reactions.
Is not
140
Succinate thiokinase cleaves high energy thioester bond of ____.
Succinyl CoA
141
During cleavage of succinyl CoA, ____ of GDP to GTP occurs.
Phosphorylation
142
During cleavage of succinyl CoA, GTP and ATP are energetically ____ by nucleoside diphosphate kinase.
Interconvertible
143
GTP can also be generated by ____.
Succinate thiokinase (substrate phosphorylation)
144
Succinate is oxidized to ____ by succinate dehydrogenase.
Fumarate
145
Coenzyme which is reduced to FADH2 during oxidation of succinate?
FAD
146
What is the only enzyme of TCA embedded in inner membrane of mitochondrion?
Succinate dehydrogenase
147
Succinate dehydrogenase functions as complex ____ of ETC.
2
148
Fumarate can be hydrated to form ____.
Malate
149
Fumarate to malate reaction can be reversed with what enzyme?
Fumarase
150
Malate is oxidized to OAA by ____ enzyme.
Malate dehydrogenase
151
Oxidation of malate yields:
Final NADH produced
152
Oxidative phosphorylation has 5 complexes, which ones are located in the inner membrane of mitochondrion?
Complexes 1-4 (part of ETC)
153
Complex 1 enzyme:
NADH dehydrogenase
154
Complex 2 enzyme:
Succinate dehydrogenase
155
Complex 3 enzyme:
Cytochrome bc1
156
Complex 4 enzyme:
Cytochrome c oxidase
157
Complex 5 enzyme:
ATP synthase
158
Coenzyme Q tail is ____.
Long, hydrophobic isoprenoid
159
Coenzyme Q carrier:
Mobile carrier
160
Coenzyme Q can accept H from ____ and ____.
FMNH2 and FADH2
161
FMNH2 is seen in which complex?
1
162
FADH2 is found in which complex?
2
163
3-carbon molecule that is one of the final products of glycolysis:
Pyruvate
164
In what part of the cell does glycolysis take place?
Cytoplasm (cytosol)
165
What is the main transformation that occurs during glycolysis?
Glycolysis produces ATP, pyruvate, and NADH by oxidizing glucose.
166
Glycolysis can or cannot occur without the presence of oxygen?
Can
167
Product of pyruvate oxidation which enters the Krebs cycle is?
Acetyl CoA
168
What part of the cell does the Krebs cycle take place in?
Mitochondria
169
The Krebs cycle produces how many ATP for 1 molecule of acetyl CoA?
12 ATP
170
What is the main stimulatory factor for the PDH complex?
Ca
171
Transport protein associated with skeletal muscle and adipose tissue?
GLUT4
172
The most potent activator of PFK1 is?
F 2,6-BP
173
Phosphoglycerate kinase is or is not a reversible reaction.
Is
174
How many ATP are consumed in glycolysis?
2
175
What is the net ATP production in glycolysis?
2
176
What are the 2 vitamins associated with NADH and FADH2?
Riboflavin and niacin
177
What is the product of glycolysis under anaerobic conditions?
Lactate
178
Where in the mitochondria does the ETC take place?
Inner mitochondrial membrane
179
What type of reaction takes smaller molecules and uses them to build more complex structures?
Anabolic
180
What functions as a cofactor that aids in the transfer of CO2 groups?
Biotin
181
NADH formed in the cytosol during glycolysis must be transported into the mitochondria via:
Malate-asparate shuttle
| G3P shuttle
182
What catalyzes the reaction for the conversion of citrate to isocitrate?
Aconitase
183
Which cofactors are used during glycolysis?
Mg and K
184
Which enzyme catalyzes reaction for the conversion from G6P to F6P?
Phosphoglucoisomerase
185
Hormonal control of GNG is regulated by?
Glucagon
186
In glycolysis, ATP production occurs with the reaction:
1,3BPG to 3PG
187
How many ATP are technically made from the TCA cycle?
0
188
Coenzyme Q accepts hydrogens from which complex?
Complex 1
189
Once OAA is converted to malate in the cytosol, what is the next regulating enzyme in GNG?
F 1,6-BP
190
Type of glycosidic bonds that humans are unable to digest?
Beta 1-4
191
What is the first rate limiting step of the TCA cycle?
Oxidative decarboxylation of isocitrate to alpha-ketoglutarate
192
L sugar chiral OH points which direction?
Left
193
Why must OAA be converted to GNG?
OAA cannot cross the mitochondrial membrane
194
Why is it necessary to phosphorylate glucose in glycolysis?
It keeps glucose from diffusing across the membrane.
195
The TCA cycle produces ____ ATP/ acetyl CoA oxidized.
12 ATP
196
3 vitamins related to PDH complex?
Riboflavin
Thymin
Niacin
197
Complex 5 of ETC involves re-entry of ____ back into the mitochondrial matrix.
Protons
198
Electron transfer terminates at which complex?
Complex 4
199
With a termination in electron transfer at complex 4, pH ____.
Decreases
200
Glucagon binding happens when glucose levels are ____.
Low
201
Pyruvate to lactate can be reversed in the ____.
Liver
