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Biochemistry

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Answer 50 questions in 15 minutes.
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Match each statement with the correct term.
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1. What are the results of CF on male fertility
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Inc NADH/NAD ratio in liver - causing diversion of pyruvate to lactate and OAA to malate - inhibiting gluconeogenesis and stimulating fatty acid synthesis. Leads to hypoglycemia and hepatic fatty liver change seen in chronic EtOH users
Males are infertile due to bilateral absence of vas deferens
Intermediate filaments

2. What does aminoacyl tRNA synthetase do the AA before and after it binds to tRNA - and what happens if it's the wrong the match
Change resulting in early stop codon
Ornithin transcarbamoylase def - x linked recesssive - other urea cycle enzymes defs are autosommal recessive
UDP glucose pyrophosphorylase
Scrutinizes - hydrolyzes the bond

3. what gene is implicated in fragile X syndrome - and What is the mutation
Brittle bone disease - most commonly lead AD with abnl type I collagen causing multiple fractures with minimal trauma - blue sclerae due to translucency of connective tissue over the choroid - hearing loss - dental imperfections due to lack of dentin
Mental retardation - hyperphagia - obesity - hypogonadism - hypotonia - deletion of normally active paternal allele on chromosome 15
Makes RNA primer on which DNA poly III can initiate replication
FMR1 gene - methylation - associated with chromosomal breakage

4. protein malnutrition resulting in skin lesions - edema and liver malfxn
Same as sprint + OXPHOS
Kwashiorkor - small child with swollen belly
HMG- CoA reductase
Proline and glycine (non glycosylated forms)

5. I g fat = ? Kcal
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Promotor - TATA box - and CAAT box - AT rich
In mitochondria - pyruvate to oxaloacetate - requires biotin - ATP - activated by acetyl coA
Nine

6. What is the physiologic role of dystrophin
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Changed AA (convservative - new AA is similar in chemical structure)
Inc insulin - dec cAMP - dec PKA
Adds an inorganic phosphate onto substrate without using ATP

7. What is the TX for PKU
Fibroblast
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
40 - 60 - 80
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase

8. What are the 3 AR forms of homocystinuria
Inc NADH/NAD ratio in liver - causing diversion of pyruvate to lactate and OAA to malate - inhibiting gluconeogenesis and stimulating fatty acid synthesis. Leads to hypoglycemia and hepatic fatty liver change seen in chronic EtOH users
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Ca/calmodulin in muscle to coordinate with muscle activity

9. characterize mitochondrial inheritance
Orotic acid to UMP
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Transmitted only through mother - all offspring of affected females may show signs of disease

10. In what cells do the respiratory burst occur
Disease
PMNs
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Williams syndrome

11. How doe NADH electrons from glycolysis and the TCA cycle enter the mitochondiria
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
EtOH dehydrogenase and acetaldehyde dehydrogenase
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia

12. cell signaling defect of fibroblast growth factor (FGF) receptor 3 - results in dwarfism - short limbs - head/trunk nl size - associated with advanced paternal age
Glucose -6 phosphate
Galactitol - galactose appears in blood and urine - can cause infantile cataracta - AR
Achondroplasia
Fed

13. What do DNA topoisomerases do
Inhibits 50S peptidyltransferase
Dec phenylalanine (contained in aspartame - Nutrasweet) inc tyrosine in diet
Ca/calmodulin in muscle to coordinate with muscle activity
Creat a nick in the helix to relieave supercoils created during replication

14. What is the fxn of vit D
Lariat shape in order and remove intron precisely and join 2 exons
B100 and E
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
ATP and alanine

15. How does ethanol induce hypoglycemia
Inc NADH/NAD ratio in liver - causing diversion of pyruvate to lactate and OAA to malate - inhibiting gluconeogenesis and stimulating fatty acid synthesis. Leads to hypoglycemia and hepatic fatty liver change seen in chronic EtOH users
Poly A polymerase - signal is AAUAA
Huntingtons
P+q = 1

16. What is the RDE of TCA cycle
Isocitrate dehydrogenase
Fructose 1 -6 bisphosphate
Terminal regions - tropocollagen
Essential fructosuria - fructokinase AR

17. What substance inside the cell reduces glutatione
Oxidative and nonoxidative - no ATP produced or used
SNP
Microtubules
NADPH

18. Where is glucokinase found - What are the Km and Vmax - and what induces it
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Glycine
Alpha - ketoglutarate dehydrogenase complex

19. NADPH are used In what 4 things
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Creat a nick in the helix to relieave supercoils created during replication

20. Where do you find elastin and What does it do
Glucose -6 phosphate
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Inc melt - dec fluidity
Stored ATP - creatine phosphate - anaerobic glycolysis

21. For eukaryotes - Where does replication begin?
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Coenzyme A - lipoamide
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Consesus sequenec of base pairs

22. What is pseudohypertrophy in the calf a result of - and What are the cardiac manifestations
Fibrofatty replacement of muscle - cardiac myopathy
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
RNA
Binds to LDL receptor - mediates VLDL secretion

23. An inability to convert orotic acid to UMP would be caused by a deficiency either of which two enzymes

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24. What substances induce phosphofructokinase
Liver - also in kidney and gut epithelium
Hereditary spherocytosis
AMP - fructose 2 -6 BP
L form

25. What is the activated carrier for methyl groups
SAM
Orotate precursor - with PRPP added later
Locus heterogeneity - ocular albinism is x- linked recessive
Assistance of upper extremities to stand up

26. Of the four possible fates for pyruvate - which ends anaerobic glycolysis as in RBCs - leukocytes - kidney medulla - lens - testes and cornea
Oxidizes substrate
Each codon specifies only 1 amino acid
Lactate
75 to 90 - cloverleaf

27. What is locus heterogeneity and give an example
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism
Binds 50S - blocking translocation
Occurs when cells in the body have different genetic makeup - can be germline mosaic - which may produce a disease that is not carried by parents somatic cells - lyonization - random X inactivation in females
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination

28. How do macrolides and clindamycin work
CGG
Binds 50S - blocking translocation
X linked frame shif mutation
Changed AA (convservative - new AA is similar in chemical structure)

29. What causes maple syrup urine disease and What does it lead to...
L form
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Fibrofatty replacement of muscle - cardiac myopathy
Dec in alpha ketoacid dehydrogenas leading to blocked degredation of branches amino acids like Ile - Leu - and Val - severe CNS defects mental retardation and death

30. What lab procedure is used to amplify desired fragment of DNA and What are the 3 steps
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
PCR - denaturation - annealing - elongation
Aminoacyl - tRNA binds A site - ribosomal rRNA catalyzes peptide bond formation - transfers growing peptide to AA in A site - ribosome advances 3 nucTIDE toward 3' end of RNA - moving peptidyl RNA to P side
Proline and glycine (non glycosylated forms)

31. Describe the replication fork
Result from phagocytic removal of heinz bodies my macs - G6PD def
Occurs when cells in the body have different genetic makeup - can be germline mosaic - which may produce a disease that is not carried by parents somatic cells - lyonization - random X inactivation in females
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

32. What two amino acids are required druing periods of growth and why
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Arg and his inc in histones Which bind negatively charged DNA
Base + ribose + phosphate (3' -5') phosphodiester bond
Neurofibromatosis type 1 (von Recklinghausens disease)

33. What defects characterize DiGeorge syndrome
Thymic - parathyroid and cardiac
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Glycogenolysis to form glucose
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid

34. What are the 2 distinct phases of the HMP shunt and How many ATP are used and produced
Read from a fixed starting point as a continuous sequence of bases
Oxidative and nonoxidative - no ATP produced or used
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Hypoxanthine to xanthing and xanthine to uric acid

35. What two enzymes are involved in EtOH metabolism
Fibrofatty replacement of muscle - cardiac myopathy
SNP
EtOH dehydrogenase and acetaldehyde dehydrogenase
Degredation of dietary TG in small intestine

36. What does the primary transcript combine with to form the spliceosome
Ribos first then deoxyribos with ribonucleotide reductase
Consesus sequenec of base pairs
SnRNPs and other proteins
Dermatitis - glossitis - and diarrhea

37. What is the Hardy Weinberg disease prevalence equation
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting
P2 +2pq+ = 1
Defect in fibrillin

38. What enzyme esterifies 2/3 of plasma cholesterol
CAG
Dermatitis - enteritis - alopecia - adrenal insuff
Uses ATP to add high energy phophate group onto substrate
LCAT (lecithin cholesterol acyltransferase)

39. What are the water soluble vitamins - which ones are stored
Glucose 6 phosphate dehydrogenase (G6PD)
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
Cleft palate - cardiac abnl - pregs test
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)

40. What are the findings in PKU
VMA
Mental retardation - growth retardation - seizures - fair skin - eczema - musty body odor
Cystathionine synthase def - dec affinity of cystathionine synthase for pyridoxal phosphate - homocystein methyltransferase def
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation

41. What is the hardy weinber heterozygote prevalence
Absence of galactose 1 phosphate uridyltransferase - accumulation of toxic substances leads to failure to thrive - jaundice - hepatomegaly - infantile cataracts - mental retardation
Alpha 1 -6 and alpha 1 -4
Phosphofructokinase 1
2pq

42. What shuttle is involved in fatty acid synthesis and What does it move From where to where
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Adenosine to inosine
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Citrate - acetyl coa from mito to cyto

43. What is regeneration of methionine depedent on...
Site of steroid synthesis and detoxification of drugs and poisons
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
B12 and folate

44. How do aminoglycosides work
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Initial is heterogenous nuclear RNA - the capped and tailed is called mRNA
By inhibiting formation of the initiation complex and cause misreading of mRNA

45. Pts with albinism are at inc risk For what cancer
Liver hepatocytes and steroid producing cells of the adrenal cortex
32 - malate aspartate shuttle
Skin
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)

46. What is the amino acid precursor for catecholamines
Keep glutathione reduced so it can detoxify free radicals and peroxides
Phenylalanine
Antioxidant - protects RBCs and membrances from free radical damage
Eu - methionine - pro - formyl - methionine

47. What does vit C def cause
Free ribosomes
In ER - glucose 6- P to glucose
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Carbomoyl phosphate synthetase II

48. What induces pyruvate kinase
F16BP
Proline and lysine - vit C
Dec in alpha ketoacid dehydrogenas leading to blocked degredation of branches amino acids like Ile - Leu - and Val - severe CNS defects mental retardation and death
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase

49. In addition to fructose and galactose - what sugards should be excluded from the diets of patients with disorders of fructose or galactose metabolism
Silencers
Sucrose = glucose + fructose - lactose = glucose + galactose
PFK - rate limiting enzyme
Neurofibromatosis type 1 (von Recklinghausens disease)

50. What bone disorder has x linked dominant inheritance
RER
Hypophophatemia rickets - vit D resistant ricketts - inc wasting of phosphate in proximal tubule - rickets like presentation
Type II
Familial hypercholesterolemia - hyperlipidemia type IIA