Cell biology - Amino acid metabolism Flashcards
when the a carbon atom of amino acid is assymetric it allows for two mirror image optical isomers known as..
a. E/Z
b. cis/trans
c. p/q
d. L/D
d.L/D
all amino acids can exist as one of two optical isomers except..
a. glycine
b. valine
c. serine
a.glycine
what forms of amino acids are found in human proteins
a,L
b.D
a,L
Lysine and hisitidine are bot examples of a ….
a. polar amino acid which a positive side chain
b. polar amino acid with an uncharged polar side chain
c. non polar amino acid with a non polar side chain
a.polar amino acid which a positive side chain
threonine is an example of a ….
a. polar amino acid which a positive side chain
b. polar amino acid with an uncharged polar side chain
c. non polar amino acid with a non polar side chain
b.polar amino acid with an uncharged polar side chain
valine, leucine, isoleucine,phenylalanine, methionine, and tryptophan are examples of a ….
a. polar amino acid which a positive side chain
b. polar amino acid with an uncharged polar side chain
c. non polar amino acid with a non polar side chain
c.non polar amino acid with a non polar side chain
what type of carbon skeleton is degraded to pyruvate / TCA intermediates as precursors for gluconeogenesis/ converted for storage
a. glucogenic
b. ketogenic
a.glucogenic
what type of amino acid has the carbon skeleton degraded to acetyle coA or acetoacetate for energy in krebs or converted to ketone bodies/fatty acids
a. glucogenic
b. ketogenic
b.ketogenic
phenylalanine is
a. glucogenic
b. ketogenic
c. both
c.both
what is glucogenic phenylalanine converted to by phenylalanine hydroxylase
a. tyrosine
b. acetoacetate
a.tyrosine
what is ketogenic phenylalanine converted to by phenylalanine hydroxylase
a. tyrosine
b. acetoacetate
b.acetoacetate
ketone body
cannot be syntheised to glucose
lack of phenylalanine hydroxylase means phenylalaine cant be converted to pyruvate . which form of pheylalanine does this happen to
a. glucogenic
b. ketogenic
a.glucogenic
what is formed instead of pyruvate when there is a lack of phenyl alanine hydroxylase in pku
a,pyruvate
b. acetoatate
c. phenylactate
d. phenylpyruvate
d.phenylpyruvate
then forms phenylactate and phenyllactate
how is PKU inherited?
a. autosomal recessive
b. autosomal dominant
c. x linked
d. polygenic
a.autosomal recessive
phenylalanine and which other substance accumulates a few days after birth in pku?
a,pyruvate
b. acetoatate
c. phenylactate
d. phenylpyruvate
d.phenylpyruvate
the heel prick test tests for pku and..
a. marfans
b. ehlers danlos
c. MCADD
c.MCADD
which of these is not supplemented in pku?
a. phenylalanine free amino acids
b. tyrosine
c. phenylalanine
c.phenylalanine
Which metabolic abnormality gives rise to the
serious disease phenylketonuria?
a) Homocysteine cannot be converted into
methionine
b) Phenylalanine cannot be converted into
tyrosine
c) Phenylalanine cannot be converted into alanine
d) Tyrosine cannot be converted into
phenylalanine
b) Phenylalanine cannot be converted into
tyrosine
what happens in step 1 of amino acid catabolism
a, a amino group transferred to a ketoglutarate to form glutamate/ oxidatively deaminated to ammonium
b. ammonium used to synthesize carbamoyl phosphate
c. carbamoyl phosphate and ornithine combine to form citrulline catalysed by OTC, citrulline then exported into cytosol where its converted to urea in 3 steps
a, a amino group transferred to a ketoglutarate to form glutamate/ oxidatively deaminated to ammonium
what happens in step 2 of amino acid catabolism
a, a amino group transferred to a ketoglutarate to form glutamate/ oxidatively deaminated to ammonium
b. ammonium used to synthesize carbamoyl phosphate
c. carbamoyl phosphate and ornithine combine to form citrulline catalysed by OTC, citrulline then exported into cytosol where its converted to urea in 3 steps
b.ammonium used to synthesize carbamoyl phosphate
what happens in step 3 of amino acid catabolism
a, a amino group transferred to a ketoglutarate to form glutamate/ oxidatively deaminated to ammonium
b. ammonium used to synthesize carbamoyl phosphate
c. carbamoyl phosphate and ornithine combine to form citrulline catalysed by OTC, citrulline then exported into cytosol where its converted to urea in 3 steps
c.carbamoyl phosphate and ornithine combine to form citrulline catalysed by OTC, citrulline then exported into cytosol where its converted to urea in 3 steps
what enzyme forms carbamoyl phosphate from ammonium in step 1 of the urea cycle inside the mitochondria?
a. lipoprtein lipase
b. phenylalanine hydroxylase
c. OTC
d. carbamoyl phosphate synthetase
d.carbamoyl phosphate synthetase
where does the urea cycle primarily occur
a. liver
b. kidney
c. spleen
a.liver
kidneys to lesser extent
what actalyses conversion of carbamoyl phosphate in combination with ornithine to citrulline
a. lipoprtein lipase
b. phenylalanine hydroxylase
c. OTC
d. carbamoyl phosphate synthetase
c.OTC
urea production requires 1 ATP - AMP conversion and how many ATP to ADP conversions
a. 1
b. 2
c. 3
d. 4
b.2
urea is excreted via which organ
a. bladder
b. liver
c. kidney
c.kidney
amino acid catobilsm pneumonic
Orange Coloured Cats Always Ask For Awesome Umbrellas
Orange Ornithine Coloured Carbamoyl Phosphate Cats Citrulline Always Aspartate (enters cycle) Ask Argininosuccinate For Fumarate (leaves cycle) Awesome Arginine Umbrellas Urea (leaves cycle)
defficiency of OTC is treated with a low protein diet how is it inherited
a. autosomal recessive
b. autosomal dominant
c. x linked recessive
d. polygenic
c.x linked recessive
what are adenine and guanine converted to in the first step of their metabolism
a,uric acid
b. urea
c. citrulline
d. xanthine
d.xanthine
what enzyme converts xanthine to uric acid?
a. lipoprtein lipase
b. phenylalanine hydroxylase
c. OTC
d. carbamoyl phosphate synthetase
e. xanthine oxidase
e.xanthine oxidase
hyperuricaemia can lead to formation of kidney stones in collecting ducts. this is elevated levels of what substance
a. serum urea
b. serum uric acid
b.serum uric acid
accumulation of uric acid or sodium urate in tissues causes gout. crystallisation of sodium urate in joints leads to..
a. gout
b. marfans
c. gouty arthiritis
c.gouty arthiritis
what drugs are used to treat gout
a. antibiotics
b. corticosteroids
c. NSAIDS
d. opiods
c. NSAIDS
what does probenecid do
a. increase renal excretion of uric acid
b. inhibit xanthine oxidase
a.increase renal excretion of uric acid
what does allupurinol do
a. increase renal excretion of uric acid
b. inhibit xanthine oxidase
b.inhibit xanthine oxidase
what is the effect of purine salvage by HGPRT on uric acid production excretion
a. increase
b. decrease
b.decrease
what happens to HGPRT activity in the rare x linked recessive inherited disorder Lesch Nyhan syndrome
a. increase
b. decrease
b.decrease
so decreased salvage and more uric acid formed
which of these is not a symptom of lesch nyhan syndrome
a. gout
b. haemoturia
c. neurologival symptoms
c.neurologival symptoms
Neurological effects of lesch nyhan are caused by..
a. uuric aci accumulation
b. lack of uric acid
c. loss of supply of purine nucleotides from salvage
c.loss of supply of purine nucleotides from salvage
Nitrogen is derived from the breakdown of?
a) Amino acids
b) Cholesterol
c) Glucose
d) Purines
e) Pyrimidines
a)Amino acids
