Metabolism Flashcards
(115 cards)
1
Q
Small molecules with a mass of 50 - 1500 Da
A
Metabolite
2
Q
Metabolome
A
Snapshot of a set of reactions that occur in a single time within a single cell
3
Q
Study of metabolites or small molecules to develope drugs, screen diseases, or personalize medicine
A
Metabolomics
4
Q
Which of the following can affect metabolism?
A. Nature of diet
B. Physical activity
C. Time of last meal intake
D. Stage of development
A
AOTA
5
Q
2 states of the body and differentiate.
A
Fed state - glucose is the metabolic fuel
Fasting state - glycogen, FA, ketone bodies, AA serve as metabolic fuel.
6
Q
Major hormones that control fuel use
A
Insulin and glucagon
7
Q
NADPH assumes importance and produces pentoses
A
Hexose monophosohate shunt (HMP)
8
Q
Intersection between catabolism and ananlism. Crossroads.
A
Amphibolic
9
Q
Products of complete oxidation
A
CO2
H2O
10
Q
T/F:
Energy is re,eased by transfer of electrons to O2
A
True
11
Q
T/F:
Energy from transfer of electronic to O2 produces heat and ATP
A
T
12
Q
Currency of cellular energy
A
ATP
13
Q
Which is the main fuel RESERVE of the body?
A. Proteins
B. Glycogen
C. Ketone bodies
D. Triacylglycerol
A
D
14
Q
Main fuel SOURCE of the body
A
Glucose
15
Q
Enumerate the 4 catabolic pathways
A
Glycolysis
Beta-oxidation
ETC
AA catabolism
16
Q
Glucose > pyruvate > acetyl CoA
A
Aerobic
17
Q
Glucose > lactate
A
Anaerobic
18
Q
FA > acetyl CoA
A
Beta oxidation
19
Q
Redistribution of reduced nitrogen
A
AA catabolism
20
Q
Enumerate the 7 anabolic pathways
A
Glycogenesis Gluconeogenesis Palmitate biosynthesis Purine and pyrimidine biosynthesis Protein biosynthesis NA biosynthesis Non - essential AA
21
Q
Intermediary metabolism
A
Process involving molecules with low molecular weight such as degradation and biosynthesis metabolites.
22
Q
Other term of Warburg effect of cancer cells
A
Tumor metabolome
23
Q
What are the effects of cancer cells stated under Warburg effect?
A
Cancer behave diff
Proliferate diff (faster than normal)
Produce more glucose and lactic acid than normal
Overexpression of enzymes
24
Q
Which of these is NOT a storage site for glycogen?
A. Adipose tissue
B. Kidney
C. Liver
D. Muscle
A
A
25
Main storage sites of glycogen
Liver and muscle
26
Other term of Acetyl CoA
FCP = Final common pathway
27
Pathway that is shunted in case of need for build up of AA
Pentose phosphate pathway (PPP)
28
The end product of glycolysis in tissue using anaerobic metabolism is?
A. CO2
B. H20
C. lactate
D. Pyruvate
C
29
System of the body that integrates or connect metabolic pathways
Blood circulation or circulatory systems
30
How does the liver maintain blood glucose concentration in between meals?
Glycogenolysis
| Gluconeogenesis
31
Synthesis of plasma protein albumin occurs in?
Liver
32
Low levels of albumin in the blood produce what symptom?
Edema
33
T/F
Low levels of albumin or rapid secretio of albumin may indicate liver problems
True
34
Role of glycogen in skeletal muscle
Acts as fuel for muscle contraction
35
Can chilomicrons be taken up by the liver efficiently?
No. Chilomicrons are NOT DIRECTLY taken up by the liver. It needs to be first metabolised by tissues that have lipase.
36
FFA can be taken up by most tissues but NOT ______ & ______.
Brain & erythrocytes
37
In the ____, newly synthesized TAGS is secreted into the circulation in _____.
Liver, VLDL
38
Enumerate the 3 Metabolic pathways that occur in the cytosol.
Glycolysis
HMP shunt
FA synthesis
39
Enumerate the 5 Metabolic pathways that occur in the mitochondria.
```
Beta oxidation
Ketogenesis
Respiration chain
ATP syntheses
CAC
```
40
Function of regulatory enzymes
Regulates the flux or amount of metabolites
41
T/F
Enzymes catalyzing non- equilibrium reactions are present in low concentration & is regulated
T
42
T/F:
Most reactions in metabolic pathways lie between equilibrium and non equilibirium
T
43
Enumerate the 5 mechanism of control
Alterations of membrane permeability
Induction of mRNA formation (promotion)
Suppression of mRNA formation
Alteration of TRANSLATION of mRNA in ribosomes
Phosphorylation/dephosphorylation rxn (inactive to active)
44
_______ inhibits lipogenesis in adipose tissue and liver
High intake of lipids
45
Can pyruvate dehydrogenase reaction to form acetyl CoA be reversed?
No. It is IRREVERSIBLE.
46
Primary substrate of gluconeogensis
Oxaloacetate
47
In gluconeogenesis, glucose is formed by non carbohydrates such as glycerol (lipids), AA, and lactate. An exception in AA are?
Leucine and lysine
48
Enumerate ketogenic AA: (PITT)
Phenylalanine
Isoleucine
Tryptophan
Tyrosine
49
Preffered metabolic fuel of the heart
Ketone bodies
50
In tissues such as the heart, metabolic fuels are oxidised in what preferred order.
Ketone bodies > fatty acids > glucose
51
What is the Heart's least preferred metabolic fuel to be oxidised?
Glucose
52
Enzyme that powers skeletal muscles to work
Creatinine phosphate
53
Recurring Process in metabolism
Convertion of substrate > product
54
Requirements for converting substrate to product
Adequate amount of substrate and enzyme
| Presence of cofactor
55
Enzyme and cofactor used to convert ADP > ATP
Creatine kinase
| Mg+3
56
2 major mechanisms of metabolism. Give examples.
Anabolism - gluconeogenesis, glycogenesis
| Catabolism - glycolysis
57
# Define:
```
Enzyme
Substrate
Active site
Allosteric site
Allosteric molecules
```
- molecule that catalyses chemical rxn
- component used to form the product
- attachment of enzyme to substrate (where S attaches)
- where allosteric molecule attaches in the enzyme
- molecules that change the active site and affects enzyme activity
58
# Define:
Positive molecules
| Negative molecules
- increase rxn rate
| - decrease rxn rate
59
How is metabolism regulated: 3 ways
1. Changing the activity of the enzyme via
- availability of the substrate
- reversible covalent enzyme modification (phosphorylation/dephosphorylation)
- allosteric enzyme modification
2. Changing the amount of enzyme via
- hormonal induction or repression of enzyme synthesis
3. Substrate availability
- S > Km = high enzyme saturation = increased rxn rate
- S < Km = low enzyme saturation = decreased rxn rate
60
Rate limiting enzyme of glycolsis
PFK-1 = Phosphofructokinase 1
61
Enzymes that increases rxn rate in glycolysis
Fructose2,5 bisPO4, AMP, and ADP
62
Enzymes that inhibit PFK1
ATP and citrate
63
Enzyme that converts glucose to glycogen when there is high glucose in blood.
Glucokinase
64
Most active lipid
FA
65
Active when dephosphorylated
Anabolic enzymes
66
Active when phosphorylated
Catabolic enzymes
67
Reciprocal regulation
2 pathways create a cycle that regulates one another through allosteric inhibitors
68
Futile cycle
When 2 pathways cannot occur at the same time due to negative benefit. Ex: glycolysis (2 atp) and pyruvate to glucose (4 atp). Magkakaroon ng negative atp
69
Where is insulin found?
Pancreatic beta cell
70
Where is glucagon found?
Pancreatic A-cell
71
Is insulin anabolic or catabolic?
Anabolic
72
Is glucagon anabolic or catabolic?
Catabolic
73
Pyruvate dehydrogenase complex active when DEphosphorylated. T/F
T
74
The brain cannot use fatty acid?
No
75
What is the preferred metabolic fuel of neurons in the fed state? Check
Glucose
76
What is the preferred metabolic fuel of neurons is the fasting state? Check
Acetoacetate
77
What is the preferred metabolic fuel of erythrocytes in the fasting state?
Glucose - most preferred by rbc in ANY STATE.
78
Most amino acids are classified as __________.
A. Glucogenic
B. Ketogenic
A
79
Why is leucine and lysine cannot be used for gluconeogenesis?
They are ketogenic. Can only yield acetyl coa on oxidation
80
How many AA are purely glucogenic
14
81
CNS and ______ always require glucose
Erythrocytes
82
Glucose provides the carbon skeletons for the glycerol of TAGs and non-essential amino acids. T/f
T
83
Markedly increase in prolonged fasting.
A. Insulin
B. Ketone bodies
C. NEFAs
B & C
84
Greek word metabole means
Change
85
2 - 4hrs after meal:
A. Fasting state
B. Fed state
C. Early fasting state
D, starvation
B
86
More than 72 hours:
A. Fasting state
B. Fed state
C. Early fasting state
D, starvation
D
87
>4 - 18hrs after meal:
A. Fasting state
B. Fed state
C. Early fasting state
D, starvation
C
88
>18 hrs - 72 hrs:
A. Fasting state
B. Fed state
C. Early fasting state
D, starvation
A
89
The average physical activity increases metabolic rate up to ________ over the basal metabolism.
40-50%
90
Beta carbon of fatty acid undergoes oxidation
Beta oxidation
91
Electrons are transferred to oxygen to produce energy
Etc
92
Redistribution of reduced nitrogen; elimination of excess urea.
AA catabolism
93
Synthesis of glycogen from glucose
Glycogenesis
94
Breakdown of fatty acids to acetyl CoA ; beta oxidation
| Synthesis of fatty acids from acetyl CoA ;____________
Palmitate biosynthesis
95
Major example of amphibolic Pathway
Citric acid cycle
96
Cancer cells can undergo glycolysis and produce ATP but it cannot produce enough energy for living cells. T/F
T
97
Important events of intermediary metabolism
20th century
21st centurry
- discovery that TCA and krebs cycle undergoes in mitochondria
- linkage to epigenetics
98
Most depleted in an overnight fast
Liver Glycogen
99
Source of reducing equivalents of NADPH for fatty acid syntheis
PPP/HMP shunt
100
What tissues is PPP most active?
Actively dividing tissues. Ex: reproductive organs (M&F) and mammary gland during lactation
101
Precursor of fatty acids, cholesterol, and other steroids.
Acetyl coa or final common pathway
102
Esterification of fatty acids with glycerol forms?
TAGs
103
Proteins supplied by the diet
Essential
104
Proteins supplied by the body
Non essential
105
Glucose and amino acids produced by the digestion of carbohydrates and proteins are absorbed by the intestinal epithelial cells and released into _________.
Hepatic portal vein
106
Excess glucose in the liver is used to synthesize __________ & _________.
FA & glycogen
107
Main lipid from diet is absorved in the _______.
Gut
108
Pathway that occurs in both cytosol and mitochondria.
Gluconeogenesis - pwede FA and ketone
FA - cytosol
Ketone- mitoc
109
Pathway that occurs in endoplasmic reticulum
TAG synthesis
110
Pathway that occurs in ribosomes
Protein sythesis
111
First rxn in a pathway is saturated with the substrate. T/F
T
112
Mechanisms of control: APAIR
113
What is the preff3r3d metabolic fuel of neurons in the FED state?
A. Acetoacetate
B. Glucose
C. Glutamate
D. Fatty acids
B
114
What is the preff3r3d metabolic fuel of neurons in the STARVATION state?
A. Acetoacetate
B. Glucose
C. Glutamate
D. Fatty acids
A
115
Kinase ; activation
| ________ ; deactivation
Phosphatases
