Biochem module 2 Flashcards
Base on IUB system, Hexokinase is what kind of enzyme?
Transferase
Major storage carbohydrate in animal
Glycogen
What equation is used for enzyme exhibiting cooperativitiy
A . Michaelis Menten
B. Hill
C. Michaelis Menten double derived reciprocal
D. All of the above
B. if ordinary, a and c
Primer protein for glycogen
Glycogenin
How to overcome competitive inhibition
Add more substate
Glycogen is a glycoproteins
False
In non competitive inhibition, A, vmax increase, km increase B. no change vmax, km decrease C. No change vmax, no change km D. Vmax decrease, no change km
D
6 membered ring structure sugar is called
Pyranose
If 5- furanose
True or false. After a chemical rxn, enzymes are consumed.
False. Enzyme catAlyzes rxn but is not consumed or PERMANENTLY altered
Storage form of glucose for plants
Starch. If human, glycogen
True or false. Cytochrome are only found in the mitochondria
False.
Where does glycogenesis occur
Liver, muscle
If rifampicin, an enzyme inducer is given concommitantly with morphine, these will happen to morphine except
A. Inc effect
B. inc metabolism
C. Inc excretion
A. Dec
Precursor for glycogen
Glucose
functions similar to those of prosthetic groups but bind in a transient, dissociable manner either to the enzyme or to a substrate
Cofactors
What is the rate limiting step in glycogenesis
Chain elongation. By glycogen synthase
Vitamin b needed for A. NAD B. FMN C. Coenzyme A D. Ketoacids E. one carbon metabolism
A. Nicotinamide B. riboflavin C. Panthotenic acid D. Thiamine E. folic acid and cobamide
Activated form of glucose
UDP glucose
True or false. Almost all enzyme are protein
True. Mostly protein Some ribozymes ( RNA enzymes)
Can glucose 1 phosphate be cleaved
No. Change it to G6P first
The ff can increase reaction rate except A. Increase temp B. increase reactant concentration C. Increase kinetic energy D. None of the above
D
Rate limiting step in glycogenolysis
Glycogen phosphorylase
How many hydrogen ion is translocated in NADH dehydrogenase
4
Product formed by debranching enzyme in glycogenolysis
Free glucose
Competitive inhibition has A. No effect on vmax, increase km B. increase vmax, no effect on km C. Decrease vmax, decrease km D, increase vmax, increase km E. no effect on vmax, no effect in km
A
Pompe’s disease lacks what enzyme
Acid maltase
phosphorylation of glucose to glucose 6-phosphate is A. Endergonic B. exergonic C. Both D. Neither
A. Needs energy from ATP.
How many ATP is used in glycogenolysis
None
Final electron acceptor in ETC
Oxygen
If Gibbs free energy is positive, it will favor
A. Substrate formation
B. product formation
Substrate
How many hydrogen ion is needed to produce 1 ATP
4
True or false. In noncompetitive inhibition, binding of the inhibitor affects binding of substrate
False. Does not affect.
True or false. Chylomicron triacylglycerol is directly taken up by liver
False. Lipoprotein lipase must first act on it
True or false. In spontaneous rxn, there is increase in entropy
True
What is the prosthetic group of peroxidase
Protoheme
Partial oxidation of fatty acids in the liver leads to
Ketone body production
How many ATP is produced from FADH2 in TCA
3
Initial electron donor in ETC
NADH
If reaction proceeds spontaneously with loss of free energy A. Gibbs is negative, exergonic B. Gibbs is positive, endergonic C. Gibbs is negative, endergonic D. Gibbs is positive, exergonic
A
serve as recyclable shuttles—or group transfer reagents—that transport many substrates from their point of generation to their point of utilization
Co enzymes
In ETC, what links the flavoproteins to cytochrome b
Ubiquinone or coenzyme Q
process of forming glucose from noncarbohydrate precursors
Gluconeogenesis
distinguished by their tight, stable incorporation into a protein’s structure by covalent or noncovalent forces
Prosthetic group
Where do non competitive inhibitor bind
Allosteric site If competitive, active site
True or false. Endergonic rxn does not need exergonic rxn to take place.
False. It cannot exist alone, must have energy source
In ETC the ff acts as proton pump except A. Complex I B. complex II C. Complex III D. Complex IV
B.
Uncouplers inhibit ETC by what mechanism
Create iodophores where hydrogen ions can go inside mitochondria thus reducing the electrochemical gradient for ATP synthase to occur
What inhibitor blocks conduction of hydrogen ion to the ATP synthase
Oligomycin
Monosaccharides are joined by A. Phosphodiester bond B. glycosidic bond C. Peptide bond D. Hydrogen bond
B.
phosphodiester bond for ATP
Peptide bond for amino acids
Under aerobic conditions, pyruvate enters the mitochondrion, where it is oxidatively decarboxylated to the two-carbon acetyl group in acetyl-CoA. This rxn is called
Transition rxn
How many ATP is produced in glycolysis
4
What organism utilize simple exergonic process
Autotrophs
Glucose is an example of A. Aldehyde B. ketone C. Carboxylic acid D. Alcohol
A. Fructose is a ketone
As you go along ETC,
A. There is an increase in electronegativity
B. There is a decrease in electronegativity
C. There is no change in electronegativity
A
In ETC, an inhibition of 1 complex will A. Slow down ETC B. Stop ETC C. Hasten ETC D. No effect
B
Lower Km will result to A. Increase affinity B. increase vmax C. Decrease affinity D. Decrease vmax
A
How many net ATP is produced in aerobic glycolysis
7
Most important carbohydrate
Glucose
How many ATP is produced in the NADH of TCA
15
Barbiturates is an inh. Of ETC complex \_\_\_\_ A. I B. II C. III D. IV
A. By inhibiting the transfer of Fes to Q
Inhibitor of complex V
Atractyloside or oligomycin
In complex IV, how many hydrogen ion are translocated
2
True or false. Enzymes are stereospecific
True.
In glycogen, what bond causes it to branch
1,6 bond
Esters of fatty acids with glycerol
Fats
If with alcohol , wax
Where does glycolysis take place
Cytosol
When a chain is said to be saturated, A. It has no double bond B. it has 1 double bond C. It has 2 double bonds D. It has 1 triple bond, 1 double bond
A.
FADH2 will start at what complex in ETC
II
Inhibitor of glyceraldehyde dehydrogenase
Iodoacetate
Amphibolic metabolism is
A. Exergonic
B. endergonic
C. Both
C. Anabolic - endergonic ; Catabolic - exergonic
ALL carboxylases require _____ as a co-factor
Biotin
All the products of digestion are metabolized to a common product called
Acetyl coA
End product of anaerobic glycolysis
Lactic acid
Energy is used in gluconeogenesis
4 ATP, 2 GTP, 2 NADH
Each glucose molecule can produce ____ ATP
32
Where does ETC take place
Inner mitochondrial membrane
Pathway to synthesize ribose
Pentose phosphate
Main fuel RESERVE of the body
Triacylglycerol
True or false. All organ can take up free fatty acids
False. Brain and erythrocytes cannot
NADH is transferred from the cytosol to the mitochondria by what transported
Glycerophosphate shuttle or malate shuttle
Where does protein synthesis take place
Endoplasmic reticulum
Acetyl-CoA is also used as the precursor for biosynthesis of the ff except a. long-chain fatty acids B. steroids C. ketone bodies D. none of the above
D
After deamination, amino nitrogen is excreted as
Urea
Glycolysis is
A. Catabolism
B. anabolism
C. Amphibolism
A
Glycolysis in RBC will yield how many net ATP
None
Dec in glycogen phosphorylase would lead to
A. Inc glycogenesis
B. dec glycogenesis
A
These organs DO NOT need insulin except A. RBC B. brain C. Liver D. Muscle E. intestinal mucosa
D. Muscle and adipose tissues need it
How many ATP is invested in glycolysis
2
How does pyruvate become lactate
Fermentation by lactate dehydrogenase
Major site of gluconeogenesis
Liver 90%, kidney 10
ATP is an inhibitor of gluconeogenesis
False. Activator along fructose 1,6 bisphosphatase
Rate limiting step in gluconeogenesis
Fructose 1,6 bisphosphate to fructose 6 phosphate
Enolase is inhibited by
Fluoride
Where does PEP carboxylase get GTP
Beta oxidation of fatty acid
True or false Increase breakdown of fat would signal gluconeogenesis
True
Muscle does NOT contribute to blood glucose
True. It has no G6P
Endoplasmic reticulum
Where is glucose 6 phosphate converted to glucose
How many ATP is used in Cori cycle
4
major precursor of glucose in ruminants
Proprionate
Priopionate is directly fed to gluconeogenesis
False.
true or false. Gluconeogenesis depends on amino acids and, to a lesser extent, on lactic acid and glycerol
True
Increase glucagon increases gluconeogenesis
True.
Glucagon stimulate glycolysis
FAlse. Inhibit
The only source of glucose during prolonged fasting
Gluconeogenesis
Inc NADH inc gluconeogenesis
False
Dietary EVEN numbered carbon fatty acids will yield propionate
False. ODD numbered so yun may carbon 15, 17, 19….
Fructose 2,6 bisphosphate would stimulate gluconeogenesis
False. Stimulate glycolysis.inh gluconeogenesis
Where can you find glucose 6 phosphates
Liver and kidney
catalyzes the conversion of glycerol to glycerol 3-phosphate
Glycerol kinase. Found only in kidney n liver
Enzyme in the Rate limiting step of glycolysis
Fructose 6 phosphate to fructose 1,6 bisphosphate
Where can you find PEP carboxylase
Mitochondria
Shape of the graph of an enzyme that exhibits cooperativitiy
SigmoidalIf ordinary enzyme, hyperbolic
combined catabolic and anabolic processes
Metabolism
The remaining free energy that is not captured as high-energy phosphate is liberated as _____
Heat
How many net ATP is produced in anaerobic glycolysis
2
Main fuel source of the body
Glucose
How many ATP is produced from the NADH of GLYCOLYSIS
5
portion of the total energy change in a system that is available for doing work
Gibb’s free energy
True or false. Metalloenzymes are metal activated enzymes
False. Metalloenzyme - prosthetic groupMetal activated enzyme - cofactors
How many hydrogen ions are translocated in complex II
None
Cyanide inhibits what complex in ETC
IV
postulates that the energy from oxidation of components in the respiratory chain is coupled to the translocation of hydrogen ions (protons, H+) from the inside to the outside of the inner mitochondrial membrane
Mitchell’s chemiosmotic theory
Most accepted theory on enzyme bonding to substrate
Induced fit by Koshland
extent of disorder or randomness of the system
Entropy
Increase in insulin would lead to
A. Inc glycogenesis
B. dec glycogenesis
A