p.19
Amino Acid Metabolism and Biosynthesis
What are ketogenic amino acids metabolized to?
Acetyl CoA or acetoacetyl CoA.
p.27
Nitric Oxide Synthesis and Function
What enzyme is responsible for the synthesis of nitric oxide?
Nitric oxide synthase (NOS).
p.41
Phenylalanine and Tyrosine Metabolism
What is the primary product of phenylalanine utilization?
Tyrosine, which accounts for about 75%.
p.27
Nitric Oxide Synthesis and Function
What is the primary function of nitric oxide (NO)?
It acts as a vasodilator.
p.49
Amino Acid Metabolism and Biosynthesis
What is the primary deficiency associated with Alkaptonuria?
Deficiency of homogentisate dioxygenase.
p.19
Amino Acid Metabolism and Biosynthesis
Which amino acids are classified as ketogenic?
Isoleucine, Leucine, Lysine, Threonine, Tryptophan, Phenylalanine, Tyrosine.
What is the genetic deficiency associated with albinism?
A deficiency of tyrosinase.
p.28
Nitric Oxide Synthesis and Function
What role does Nitric Oxide play in the body?
It acts as a cell messenger.
p.38
Amino Acid Metabolism and Biosynthesis
What does creatinine excretion indicate?
It is generally constant and proportional to muscle mass.
p.19
Amino Acid Metabolism and Biosynthesis
Can animals convert acetyl CoA or acetoacetyl CoA to pyruvate?
No, animals cannot convert them to pyruvate.
p.14
Amino Acid Metabolism and Biosynthesis
What is the role of transaminations in amino acid metabolism?
They facilitate the transfer of amino groups between amino acids and α-keto acids.
p.18
Amino Acid Metabolism and Biosynthesis
What are glucogenic amino acids metabolized to?
α-ketoglutarate, pyruvate, oxaloacetate, fumarate, or succinyl CoA.
p.42
Phenylalanine and Tyrosine Metabolism
What is Phenylketonuria (PKU) caused by?
Deficiency of phenylalanine hydroxylase.
p.52
Serotonin and Melatonin Biosynthesis
Where is serotonin primarily formed in the body?
In the brain, platelets, smooth muscle, and gastrointestinal tract.
p.12
Amino Acid Metabolism and Biosynthesis
What compounds can the nitrogen from glutamine be donated to?
Purines, pyrimidines, and other amino acids.
p.44
Amino Acid Metabolism and Biosynthesis
What happens to neurons in the basal ganglia in Parkinsonism?
There is a loss of neurons, leading to decreased dopamine levels.
p.14
Amino Acid Metabolism and Biosynthesis
What enzyme catalyzes the transamination of glutamate to pyruvate?
Alanine Aminotransferase (ALT).
p.15
Essential and Non-Essential Amino Acids
What are the two main classifications of amino acids based on their necessity for the body?
Essential and Non-essential amino acids.
p.15
Amino Acid Metabolism and Biosynthesis
What are the two metabolic classifications of amino acids based on their role in energy production?
Glucogenic and Ketogenic amino acids.
p.55
Serotonin and Melatonin Biosynthesis
What factors control the synthesis of melatonin?
Light, among other factors.
p.47
Amino Acid Metabolism and Biosynthesis
What is the function of Catechol-O-Methyl Transferase (COMT)?
It terminates the activity of catecholamines.
p.44
Amino Acid Metabolism and Biosynthesis
What is L-DOPA used for in relation to Parkinsonism?
It is used to increase dopamine levels in the brain.
p.14
Amino Acid Metabolism and Biosynthesis
What are the products of the transamination of glutamate and pyruvate?
α-Ketoglutarate and alanine.
p.44
Amino Acid Metabolism and Biosynthesis
What is the role of Carbidopa in the treatment of Parkinsonism?
Carbidopa blocks the conversion of L-DOPA to dopamine outside the brain, allowing more L-DOPA to reach the brain.
p.36
Amino Acid Metabolism and Biosynthesis
In which types of cells are spermidine and spermine found?
In virtually all prokaryotic and eukaryotic cells.
p.55
Serotonin and Melatonin Biosynthesis
How does melatonin affect ovarian function?
It suppresses ovarian function.
p.30
Serotonin and Melatonin Biosynthesis
What is the role of tetrahydrofolate (FH4) in the conversion of Serine to Glycine?
It acts as a cofactor in the reaction.
p.38
Urea Cycle and Ammonia Detoxification
What does the Creatinine Clearance Test assess?
Kidney function by comparing creatinine levels in urine and blood.
p.32
Amino Acid Metabolism and Biosynthesis
What is the role of Methionine Synthase?
It converts Homocysteine to Methionine and is dependent on Vitamin B12.
p.33
Amino Acid Metabolism and Biosynthesis
What is the relationship between high blood levels of homocysteine and health?
High blood levels of homocysteine are associated with cardiovascular disease and death.
p.37
Amino Acid Metabolism and Biosynthesis
What are the main components involved in the synthesis of Creatine?
Arginine, Glycine, and Ornithine.
p.48
Phenylalanine and Tyrosine Metabolism
What enzyme catalyzes the conversion of p-hydroxyphenylpyruvate to homogentisate?
p-Hydroxyphenylpyruvate dioxygenase.
p.47
Amino Acid Metabolism and Biosynthesis
What is the inactive metabolite associated with COMT?
S-Adenosyl-homocysteine (SAM).
p.14
Amino Acid Metabolism and Biosynthesis
What enzyme catalyzes the transamination of glutamate to oxaloacetate?
Aspartate Aminotransferase (AST).
p.51
Serotonin and Melatonin Biosynthesis
What is produced after the decarboxylation of 5-Hydroxy-tryptophan?
5-Hydroxy-tryptamine (5-HT), also known as serotonin.
p.22
Urea Cycle and Ammonia Detoxification
What are the reactants in the urea cycle equation provided?
Ammonia, carbon dioxide, and 3 ATP.
p.54
Serotonin and Melatonin Biosynthesis
What is 5-HIAA?
5-Hydroxyindole acetic acid, a metabolite of serotonin.
What is the primary function of melanin in the skin?
It protects against sunlight.
p.33
Amino Acid Metabolism and Biosynthesis
What is homocysteinuria?
A rare condition caused by a deficiency of cystathionine beta-synthase.
p.30
Serotonin and Melatonin Biosynthesis
What key intermediate is formed during the conversion of Serine to Glycine?
N5, N10-Methylene tetrahydrofolate (FH4).
p.8
Digestion of Dietary Proteins
What is the first step in the metabolism of dietary proteins?
Digestion to amino acids.
p.14
Amino Acid Metabolism and Biosynthesis
What are the products of the transamination of glutamate and oxaloacetate?
α-Ketoglutarate and aspartate.
p.21
Nitric Oxide Synthesis and Function
What is the role of GABA in the brain?
It acts as an inhibitory neurotransmitter.
p.34
Methionine Metabolism
What is the role of S-Adenosyl Methionine (SAM) in methionine metabolism?
SAM acts as a methyl donor in various methylation reactions.
p.53
Serotonin and Melatonin Biosynthesis
What are common symptoms of Eosinophilia-myalgia syndrome?
Severe muscle and joint pain, weakness, swelling of the arms and legs, fever, skin rash, and eosinophilia.
p.30
Serotonin and Melatonin Biosynthesis
What are the biosynthetic pathways that utilize Glycine?
Biosynthesis of purines and formation of thymine.
p.42
Phenylalanine and Tyrosine Metabolism
What are some symptoms of PKU?
Seizures, mental retardation, brain damage.
p.23
Urea Cycle and Ammonia Detoxification
What is the primary role of the Urea Cycle?
To synthesize arginine and detoxify ammonia.
p.32
Amino Acid Metabolism and Biosynthesis
What is the significance of PLP in the context of Cystathionine?
Cystathionine β-synthase is PLP-dependent.
p.31
Amino Acid Metabolism and Biosynthesis
What potential role does Sarcosine have in medical research?
It is being studied as a possible biomarker for prostate cancer.
p.37
Amino Acid Metabolism and Biosynthesis
What enzyme is responsible for converting Arginine and Glycine into Guanidoacetate?
Arginine-glycine transamidinase.
p.30
Serotonin and Melatonin Biosynthesis
Why is the conversion of Serine to Glycine important?
It is important in the biosynthesis of heme, porphyrins, and purines.
p.8
Protein Degradation In Proteasomes Following Tagging With Ubiquitin
What happens to proteins that are no longer needed?
They undergo degradation in proteasomes.
p.24
Urea Cycle and Ammonia Detoxification
What is the primary function of the Urea Cycle?
To convert ammonia (NH3) into urea for excretion.
p.33
Amino Acid Metabolism and Biosynthesis
What role does folate play in relation to homocysteine?
Folate enhances the conversion of homocysteine to methionine.
p.28
Nitric Oxide Synthesis and Function
What is the mechanism of action of Sildenafil (Viagra)?
It blocks phosphodiesterase-5, increasing levels of cGMP in vascular smooth muscle.
p.14
Amino Acid Metabolism and Biosynthesis
Why are blood levels of aminotransferases important?
They are indicators of liver disease.
p.12
Amino Acid Metabolism and Biosynthesis
What is the role of NH4+ in the incorporation process?
It is converted into NH3 and used in the synthesis of glutamine.
p.30
Serotonin and Melatonin Biosynthesis
What is the process of converting Serine to Glycine called?
Serine hydroxymethyl transferase (PLP-dependent).
p.38
Amino Acid Metabolism and Biosynthesis
What is creatine primarily used for?
As a dietary supplement to improve athletic performance.
p.40
Phenylalanine and Tyrosine Metabolism
What enzyme converts Phenylalanine to Tyrosine?
Phenylalanine-4-monooxygenase (Phenylalanine hydroxylase).
p.21
Nitric Oxide Synthesis and Function
What is GABA?
Gamma-aminobutyrate, an important inhibitory neurotransmitter in the brain.
p.53
Serotonin and Melatonin Biosynthesis
What syndrome is associated with L-Tryptophan?
Eosinophilia-myalgia syndrome (EMS).
p.47
Amino Acid Metabolism and Biosynthesis
What are the excretion products of catecholamines a result of?
The combined actions of MAO and COMT.
p.35
Polyamine Biosynthesis
What is the starting compound for polyamine biosynthesis?
Ornithine (from the urea cycle).
p.54
Serotonin and Melatonin Biosynthesis
What type of tumor is a carcinoid tumor?
A malignant gastrointestinal tumor.
p.52
Serotonin and Melatonin Biosynthesis
What role does serotonin play in the brain?
It regulates sleep, mood, and appetite.
p.11
Amino Acid Metabolism and Biosynthesis
What is the first step in the incorporation of NH4+ into organic compounds?
NH4+ + HCO3- + 2 ATP → NH2CO2PO3^2- + 2 ADP + Carbamoyl Phosphate + Pi + 2 H+.
p.9
Digestion of Dietary Proteins
What does trypsin cleave?
Chymotrypsinogen to chymotrypsin, proelastase to elastase, and procarboxypeptidase to carboxypeptidase.
p.52
Serotonin and Melatonin Biosynthesis
What is the function of serotonin in platelets?
It is involved in platelet aggregation and vasoconstriction.
p.16
Essential and Non-Essential Amino Acids
How can non-essential amino acids be formed in the body?
From α-keto acids by transamination and subsequent reactions.
p.49
Amino Acid Metabolism and Biosynthesis
What condition may develop in adulthood for individuals with Alkaptonuria?
Tendency toward arthritis.
p.44
Amino Acid Metabolism and Biosynthesis
What is the significance of the Blood-Brain Barrier in the context of L-DOPA?
L-DOPA can cross the Blood-Brain Barrier to increase dopamine levels in the brain.
p.34
Methionine Metabolism
What is produced when S-Adenosyl Methionine (SAM) is decarboxylated?
Decarboxylated SAM and CO2.
p.18
Amino Acid Metabolism and Biosynthesis
What is the role of glucogenic amino acids in metabolism?
They can be converted into glucose or intermediates of the citric acid cycle.
p.31
Amino Acid Metabolism and Biosynthesis
When was Sarcosine identified as a possible biomarker for prostate cancer?
February 12, 2009, in Nature.
Where is melanin primarily formed in the body?
In skin (melanocytes), eyes, and hair.
p.13
Amino Acid Metabolism and Biosynthesis
What are the products of a transamination reaction?
Amino Acid 2 and a-keto Acid 1.
p.11
Amino Acid Metabolism and Biosynthesis
What is the role of Glutamate dehydrogenase in the incorporation of NH4+?
It catalyzes the conversion of α-Ketoglutarate to Glutamate.
p.40
Phenylalanine and Tyrosine Metabolism
What are the substrates required for the conversion of Phenylalanine to Tyrosine?
O2, H2O, NADPH, and Tetrahydrobiopterin (BH4).
p.46
Nitric Oxide Synthesis and Function
In which foods is Tyramine naturally found?
Several types of cheese, beer, and red wine.
p.35
Polyamine Biosynthesis
What enzyme is responsible for converting ornithine to putrescine?
Ornithine decarboxylase (ODC).
p.56
Nicotinic Acid Synthesis and Function
What important coenzyme is synthesized from nicotinic acid?
Nicotinamide adenine dinucleotide (NAD).
p.17
Essential and Non-Essential Amino Acids
What are essential amino acids?
Amino acids required in the diet that humans cannot synthesize.
p.33
Amino Acid Metabolism and Biosynthesis
How may dietary folate deficiency relate to homocysteine levels?
Dietary folate deficiency may lead to high levels of homocysteine.
What is Dopaquinone in the melanin formation pathway?
A highly colored polymeric intermediate.
p.28
Nitric Oxide Synthesis and Function
What is the relationship between Nitroglycerin and Nitric Oxide?
Nitroglycerin is converted to Glycerin and NO, which promotes vasodilation.
p.56
Nicotinic Acid Synthesis and Function
What is the chemical structure of tryptophan involved in its metabolism?
N H CH2 CHCO2 - NH3 + Tryptophan.
p.46
Nitric Oxide Synthesis and Function
How does Tyramine affect blood pressure in individuals taking MAO inhibitors?
It causes nor-epinephrine release, leading to increased blood pressure.
p.13
Amino Acid Metabolism and Biosynthesis
What are the reactants in a transamination reaction?
Amino Acid 1 and a-keto Acid 2.
p.53
Serotonin and Melatonin Biosynthesis
What was the cause traced in cases of Eosinophilia-myalgia syndrome?
Impurities in L-Tryptophan.
p.8
Protein Degradation In Proteasomes Following Tagging With Ubiquitin
What is the role of ubiquitin in protein degradation?
It tags proteins for degradation.
p.24
Urea Cycle and Ammonia Detoxification
What are the starting materials for the Urea Cycle?
Ammonia (NH3) and carbon dioxide (CO2).
p.10
Amino Acid Transport and Absorption
What is the volume of the lumen in the context of amino acid absorption?
10 Lumen (referring to the intestinal lumen).
p.37
Amino Acid Metabolism and Biosynthesis
What is the role of S-Adenosylhomocysteine in the synthesis of Creatine?
It is a product of the reaction involving SAM and ATP.
p.13
Amino Acid Metabolism and Biosynthesis
What cofactor is required for the aminotransferase enzyme in transamination?
Pyridoxal phosphate (PLP).
p.33
Amino Acid Metabolism and Biosynthesis
What are some symptoms of homocysteinuria?
Dislocated optical lenses, mental retardation, osteoporosis, and cardiovascular disease.
p.16
Essential and Non-Essential Amino Acids
What are non-essential amino acids?
Amino acids that are not required in the diet.
p.31
Amino Acid Metabolism and Biosynthesis
What enzyme is associated with the metabolism of Sarcosine?
Glycine N-Methyltransferase.
p.28
Nitric Oxide Synthesis and Function
How does Nitric Oxide induce vasodilation?
By activating guanylyl cyclase to produce cGMP.
p.18
Amino Acid Metabolism and Biosynthesis
Which amino acids are considered glucogenic?
Aspartate, Asparagine, Arginine, Phenylalanine, Tyrosine, Isoleucine, Methionine, Valine, Glutamine, Glutamate, Proline, Histidine, Alanine, Serine, Cysteine, Glycine, Threonine, Tryptophan.
p.35
Polyamine Biosynthesis
What cofactor is required by ornithine decarboxylase?
Pyridoxal phosphate (PLP).
p.48
Phenylalanine and Tyrosine Metabolism
What are the products of the cleavage of the aromatic ring during homogentisate metabolism?
Fumarate and acetoacetate.
p.42
Phenylalanine and Tyrosine Metabolism
What is the primary treatment for PKU?
Limit phenylalanine intake.
p.16
Essential and Non-Essential Amino Acids
Name three examples of non-essential amino acids.
Alanine, Asparagine, Aspartate.
p.20
Amino Acid Metabolism and Biosynthesis
What is the role of Glutamine synthase?
It converts Glutamate to Glutamine.
p.51
Serotonin and Melatonin Biosynthesis
What is the role of oxygen (O2) in tryptophan metabolism?
It is required by tryptophan hydroxylase for the conversion to 5-Hydroxy-tryptophan.
p.45
Amino Acid Metabolism and Biosynthesis
What are MAO inhibitors used for?
They are useful in the treatment of depression.
What role does histamine play in allergic responses?
It mediates vasodilation and bronchoconstriction via H1 receptors.
p.52
Serotonin and Melatonin Biosynthesis
What class of drugs is commonly used to treat depression by affecting serotonin?
Serotonin-selective reuptake inhibitors (SSRIs).
p.20
Urea Cycle and Ammonia Detoxification
What is the relationship between Arginine and the Urea Cycle?
Arginine is involved in the Urea Cycle.
p.34
Methionine Metabolism
What is the significance of the methyl donation process in methionine metabolism?
It is crucial for the regulation of gene expression and the synthesis of various biomolecules.
p.11
Amino Acid Metabolism and Biosynthesis
What are the products of the reaction involving NADP+ and NADPH?
NADP+ is reduced to NADPH + H+.
p.45
Amino Acid Metabolism and Biosynthesis
What is the role of aldehyde dehydrogenase in relation to MAO?
It is involved in the metabolism of aldehydes produced by MAO activity.
p.49
Amino Acid Metabolism and Biosynthesis
What is the symptom status of Alkaptonuria in childhood?
Asymptomatic in childhood.
p.38
Urea Cycle and Ammonia Detoxification
Why is the Creatinine Clearance Test important in medicine?
It helps determine dosing of several drugs in patients with impaired renal function.
p.34
Methionine Metabolism
What enzyme synthesizes S-Adenosyl Methionine (SAM)?
S-Adenosyl methionine synthase.
p.53
Serotonin and Melatonin Biosynthesis
What serious outcomes have been reported in cases of Eosinophilia-myalgia syndrome?
Many hundreds of cases and several deaths.
p.11
Amino Acid Metabolism and Biosynthesis
What enzyme is involved in the reaction of NH4+ with Carbamoyl Phosphate?
Carbamoyl Phosphate Synthase I (CPS-I).
What is histamine formed from?
Histidine through decarboxylation.
p.32
Amino Acid Metabolism and Biosynthesis
What is produced from the reaction involving Cystathionine lyase?
Cysteine (Non-essential) and β-Hydroxybutyrate.
p.10
Amino Acid Transport and Absorption
Where do amino acids go after intestinal absorption?
They enter the blood for transport.
p.37
Amino Acid Metabolism and Biosynthesis
Where does the conversion of Guanidoacetate to Creatine occur?
In the liver, via Guanidoacetate Methyltransferase.
p.56
Nicotinic Acid Synthesis and Function
What is the role of nicotinic acid in the body?
It is a precursor for NAD, which is essential for metabolic processes.
p.23
Urea Cycle and Ammonia Detoxification
Which enzyme catalyzes the formation of N-Acetylglutamate?
N-Acetylglutamate synthase.
p.35
Polyamine Biosynthesis
What is the role of spermidine synthase in polyamine biosynthesis?
It converts putrescine to spermidine.
p.25
Urea Cycle and Ammonia Detoxification
What can cause hyper-ammonemia?
Defects in urea cycle enzymes.
p.8
Amino Acid Metabolism and Biosynthesis
What are the end products of protein metabolism?
Amino acids and metabolites.
p.43
Catecholamine Biosynthesis
What role do DOPA, dopamine, norepinephrine, and epinephrine play in the body?
They are all neurotransmitters.
p.17
Essential and Non-Essential Amino Acids
What is the role of Lysine in the human diet?
It is one of the essential amino acids required in the diet.
p.13
Amino Acid Metabolism and Biosynthesis
What is the role of a-ketoglutarate in transamination?
It acts as a keto acid acceptor.
p.35
Polyamine Biosynthesis
What is the role of S-adenosylmethionine (SAM) in polyamine biosynthesis?
It acts as a methyl donor in the synthesis of spermidine and spermine.
p.16
Essential and Non-Essential Amino Acids
What role do essential amino acids play in the formation of non-essential amino acids?
They serve as precursors for some non-essential amino acids like Cysteine and Tyrosine.
p.17
Essential and Non-Essential Amino Acids
What is the significance of Methionine in human nutrition?
It is one of the essential amino acids required in the diet.
p.26
Urea Cycle and Ammonia Detoxification
What is uremia?
Elevated BUN in both acute and chronic renal failure.
p.26
Urea Cycle and Ammonia Detoxification
What can cause faulty urine formation and excretion?
Various diseases that damage the kidney.
p.24
Urea Cycle and Ammonia Detoxification
What is the significance of ornithine transcarbamoylase in the Urea Cycle?
It catalyzes the reaction between carbamoyl phosphate and ornithine.
p.17
Essential and Non-Essential Amino Acids
Why are essential amino acids important for humans?
Humans are incapable of forming the requisite carbon skeleton.
p.45
Amino Acid Metabolism and Biosynthesis
What is the function of Monoamine Oxidase (MAO)?
MAO is involved in the metabolism of neurotransmitters such as norepinephrine, epinephrine, and dopamine.
p.36
Amino Acid Metabolism and Biosynthesis
What is the function of a-Difluoromethyl-ornithine (DFMO)?
It inhibits the enzyme ODC.
p.34
Methionine Metabolism
What is the relationship between methionine and S-Adenosyl Homocysteine?
Methionine is converted to S-Adenosyl Homocysteine after donating a methyl group.
p.32
Amino Acid Metabolism and Biosynthesis
What is the relationship between Methionine and Homocysteine?
Methionine can be converted to Homocysteine.
p.48
Phenylalanine and Tyrosine Metabolism
What is the role of ascorbate in the reaction involving homogentisate dioxygenase?
It acts as a cofactor in the reaction.
p.42
Phenylalanine and Tyrosine Metabolism
What compound is produced in excess due to PKU?
Phenylpyruvate (found in urine).
p.34
Methionine Metabolism
What type of enzymes are methyl-transferases?
Enzymes that transfer methyl groups from SAM to various substrates.
p.29
Serotonin and Melatonin Biosynthesis
What is the significance of 3-Phosphoserine in the pathway?
It is an intermediate in the formation of Serine.
p.17
Essential and Non-Essential Amino Acids
What is Threonine's role in the human body?
It is an essential amino acid required in the diet.
p.29
Serotonin and Melatonin Biosynthesis
What is the effect of the pathway on Glutamate?
It converts Glutamate to α-Ketoglutarate.
p.42
Phenylalanine and Tyrosine Metabolism
What screening is mandated for newborns in relation to PKU?
Screening of all newborns for PKU.
p.52
Serotonin and Melatonin Biosynthesis
What are some conditions treated with drugs affecting serotonin actions?
Depression, migraine, schizophrenia, obsessive-compulsive disorders, and chemotherapy-induced emesis.
p.36
Amino Acid Metabolism and Biosynthesis
What condition is DFMO (Eflornithine) used to treat?
Pneumocystis carinii infections.
p.43
Catecholamine Biosynthesis
What is the final product of catecholamine biosynthesis?
Epinephrine (Adrenaline).
p.23
Urea Cycle and Ammonia Detoxification
What is the role of Carbamoyl phosphate in the Urea Cycle?
It is an activated form of ammonia that enters the cycle.
p.48
Phenylalanine and Tyrosine Metabolism
What is the significance of transamination in the formation of homogentisic acid?
It converts tyrosine to p-hydroxyphenylpyruvate.
p.29
Serotonin and Melatonin Biosynthesis
What is the role of NAD+ in the formation of Serine?
It is reduced to NADH during the process.
p.24
Urea Cycle and Ammonia Detoxification
Which enzyme catalyzes the formation of argininosuccinate?
Argininosuccinate synthase.
p.43
Catecholamine Biosynthesis
What is the role of S-Adenosylhomocysteine in catecholamine biosynthesis?
It acts as a methyl donor in the methyl transferase reaction.
p.17
Essential and Non-Essential Amino Acids
Name two essential amino acids that are also precursors for neurotransmitters.
Phenylalanine and Tryptophan.
Name two H2 blockers.
Cimetidine (Tagamet) and ranitidine (Zantac).
p.25
Urea Cycle and Ammonia Detoxification
What are two amino acids that can help increase ammonia excretion?
L-arginine and L-citrulline.
p.29
Serotonin and Melatonin Biosynthesis
What is the role of Phosphatase in the formation of Serine?
It removes phosphate groups from intermediates.
p.26
Urea Cycle and Ammonia Detoxification
What happens to ions like Na+ and Cl- during hemo-dialysis?
They are maintained at the same concentration in the dialyzing solution, preventing net diffusion out of circulation.
p.17
Essential and Non-Essential Amino Acids
List three essential amino acids.
Isoleucine, Leucine, Valine.
p.45
Amino Acid Metabolism and Biosynthesis
Which neurotransmitters are affected by MAO in the brain?
Dopamine, norepinephrine, and serotonin.
p.10
Protein Synthesis and Functional Proteins
What is the primary function of amino acids in the body?
To serve as building blocks for proteins.
p.25
Urea Cycle and Ammonia Detoxification
What are the potential consequences of hyper-ammonemia in neonates?
Severe neurological defects.
p.52
Serotonin and Melatonin Biosynthesis
How do some hallucinogens, like LSD, interact with serotonin?
They act as serotonin agonists.
p.23
Urea Cycle and Ammonia Detoxification
What are the four main steps involved in the Urea Cycle?
Formation of Carbamoyl phosphate, conversion to Citrulline, formation of Argininosuccinate, and conversion to Arginine.
p.26
Urea Cycle and Ammonia Detoxification
What is the role of hemo-dialysis in relation to BUN?
It removes soluble urea and other waste products from the blood.
Name two H1 blockers.
Diphenhydramine (Benadryl) and Loratidine (Claritin).
p.45
Amino Acid Metabolism and Biosynthesis
What are the urinary metabolites associated with MAO activity?
Vanillylmandelic acid (VMA) and Homovanillic acid (HVA).
p.10
Digestion of Dietary Proteins
What role do oligopeptides play in digestion?
They are intermediate products that are further broken down into amino acids.
What effect does histamine have on gastric acid secretion?
It stimulates secretion via H2 receptors.
p.37
Amino Acid Metabolism and Biosynthesis
What is the non-enzymatic process related to Creatinine?
Creatinine is formed non-enzymatically in muscle.
p.24
Urea Cycle and Ammonia Detoxification
What role does arginase play in the Urea Cycle?
It catalyzes the conversion of arginine to urea and ornithine.
p.26
Urea Cycle and Ammonia Detoxification
How does congestive heart failure affect BUN levels?
It leads to low blood pressure and reduced renal filtration, increasing BUN.
p.29
Serotonin and Melatonin Biosynthesis
What inhibits the formation of Serine?
Certain metabolites in the pathway.
p.23
Urea Cycle and Ammonia Detoxification
What is the significance of N-Acetylglutamate in the Urea Cycle?
It acts as an allosteric activator of Carbamoyl phosphate synthetase I (CPS-I).
p.24
Urea Cycle and Ammonia Detoxification
What is the relationship between the Urea Cycle and the TCA Cycle?
Fumarate, a product of the Urea Cycle, enters the TCA Cycle.
