Biochem Flashcards
High serum lvl of alaine aminotranferase indicates only liver damage
F
Aminotranferase reactions are irreversible
F
Aminotranferase requires pyrodoxal phosphate a co factor derived from B6
True
Co factor of aminotranferase is attached to the enzyme via amide bond
F
Glutamine is the most common product of aminotranferase reactions
F
Choose amino acid used for protein synthesis but can’t be for humans except by metabolism of another amino acid which is impossible in normal metabolitoes
Tyrosine and cysteine
2 nitrogens in urea enter urea synthesis pathway in what molecular form
One as amonia and one as alpha amino group of aspartate
Person with phenylketonuria consumes food with high phenylalanine leads to
Phenylpyruvate
Oxidation of fatty acids is highest between meals and lower in well fed states
True
What is bilirubin conjugated with in jaundice
Glucuronic acid
Carbs are beneficial because food with sugar tastes better
F
Carbs are required for fat oxidation
F
Carbs prevent hypoglycemia
T
Carbs improve renal functions
F
Carbs improve urea synthesis in the liver
F
Nitric oxide and urea have in common this amino a id which is used as an immediate precursor
Arginine
Which of the following incorrectly pairs a pathway with one of it’s regulated enzymes
Urea cycle carbamoyl phosphate synthetase ll CPS II
Glucogenesis: which of the following incorrectly pairs a glycotic enzyme with the glucogenic enzyme that catalizes the reverse
Pyruvate kinase pyruvate dehydrogenase (turns pyruvate to acetylcoa)
Which one is the precursor of potent vasoconstrictor serotonin
Tryptophan
Which of the following essential dietary factors is a precursor for a compound as a carrier of the acetate group (two-carbon fragment)?
A. Methionine
B. Thiamine
C. Folic acid
D. Biotin
E. Pryidoxine
Thiamine
Choose the wrong statement in the transamination of amino acids.
A. Pyridoxal phosphate is a cofactor
(B) The reaction is tightly controlled by allosterie effectors
© The amino group acceptor is typically an a-keto acid alpha keto glutarate
D. Ammonia is neither consumed nor produced
E. Proline is one of few amino acids which are not subjected to transamination
(B) The reaction is tightly controlled by allosterie effectors
Which one of the following amine acids is purely Ketogenic regarding the fate of carbon skeletons?
A. Isoleucine
B. Tyrosine
C. Alanine
D.Leucine
E. Gycine
(D? Leucine
- Choose the wrong statement regarding the digestion of proteins?
A. Pepsinogen is activated by autoactivation (pH 2) or autocatalysis
B. The major products of peptic hydrolysis are mostly large peptides
C. Trypsin and chymotrypsin are secreted by the pancreas as inactive zymogens
D. Enteropeptidase (enterokinase) activates pancreatic trypsinogen
dipeptides / small
Most of the digested proteins are absorbed in the intestines in the form of polypeptides
Most of the digested proteins are absorbed in the intestines in the form of polypeptides
Which enzymatic activity in the pentose phosphate pathway requires thiamine pyrophosphate (TPP) as a cofactor?
A. Glucose 6-phophate dehydrogenase (G6PD)
B. 6-Phosphogluconate dehydrogenase
C.Transketolase
D. Transaldolase
E. Phosphopentose isomerase
Transketolase
Which polysaccharide cannot be hydrolysed by humans due to the presence ofthep finkage in repeating units?
A. Amylopectin
B. cellulose
D. Starch
E. Glycogen
Cellulose
A protein X is formed by two chains with 80 amino acids in one chain and 58 in the other.
These two chains are linked by disulfide bonds and all the essential amino acids are present in the structure. but not all the non-essential amino acids. With this information, how can you classify this protein according to the nutritional value?
A. A globular protein
B. A fibrous protein
C. A conjugated protein
D. An incomplete protein
E.A complete protein
(E) A complete protein
- An amino acid that yieldsfacetoacetyl Co/ during the catabolism of its carbon skeleton would be considered as one of the following. Choose the correct answer.
A. Glycogenic
B. Ketogenic
C. Glycogenic and ketogenic
D. Neither glycogenic nor ketogenic
E. Essential
Ketogenic
ketogenic and glucogenic that yield acetoacety
tryptophan, phenylalanine, tyrosine
- Which carriers are used to transport the NH, produced in muscle degradation of nitrogenated compounds through blood to the liver?
A. Alanine and glutamine
B. Urea and alanine
C. NH: and glutamate
D. Glutamate and glutamine
E. a-Ketoglutarate and urea
Alanine and glutamine
- Choose the correct answer for the necessary coenzyme for transmination reactions
A.Prridoxal phosphate
B. Thiamine pyrophosphate
C.Coenzyme A
D. Tetrahydrobiopterin
E. Folate
Prridoxal phosphate
Amino acids are requared for the syntheses of other nitrogen compoundse
T
Essential amino scads must be obtained in the diet daily.
T
Nitrogen is continuously lost from the body regard less of the protein intake amount
T
…. proteins have the highest biological value
Animal origin
Protein degradation to provide energy results in
Loss of other functions
The carbon atoms of serine can, appear in all of the following except one of them. Indicate which ore is that?
A. Pyruvite
B.leucine
C.glycine
D.sphyngomylin
Ephosphatidyl ethanolamine
sphyngomylin
Which of the following is an intermediate in the degradation of lysine?
Seccharopine
All amino acids are glucogenic.
F
Amino acid catabolisen is increased during…
Starvation
All amino acids are essential amino acids.
F
The major excrctory end profact of acmino acid catabolism is
Urea
Tissue proccin synthesis is decreased duting periods of growth.
F
Besides diet restrictions, bat warranting an apocopriate amount of the essential amine aids, which of the following amino acids you should supelement in higher quantities than in a normal dict. since it is essential for a PRU (obenytectonuna) patient.
Tyrosine
The diet must supply only enough phenylalanine and
tyrosine to meet the needs for
protein synthesis.
Which of the following is an example of the oxidative desination reaction taking part in amino acids metabolism
Glutamate = alpha-Ketoglunarate + NH3
Glutamate=hexanoic acid+NH3
Glutamate dehydrogenase
Pepsinogen us activated by
Auto activated ph2
Autocatalysis
Major products of peptiv hydrolysis
Large peptides
Trypsin amd chemotrypsin are secreted by… as…
Pancreas
Inactive zygomens
Enterokinase activates
Pancreatic trypsinogen
….. is an amino acid not subjectted to transmination
Proline
