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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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This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. congenital microdeletion of long arm of chromosoe 7 with findings of elfin facies - mental retardation - hypercalcemia - well developed verbal skills - extreme friendliness with strangers - cardiovascular problems
Williams syndrome
Prokaryotic only - elongates leading strand by adding deoxnucTIDE to the 3' end. Elongates lagging strand until it reaches primer of preceeding fragment. 3' to 5' exonuclease activity 'proofreads' each added nucTIDE
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Liver and leafy veggies

2. What enzymes metabolize fatty acids and amino acids
Inc melt - dec fluidity
Same as sprint + OXPHOS
Conversion of NE to epi
Acetoacetate and beta hydroxybutyrate

3. What does an umabiguous genetic code refer to...
Each codon specifies only 1 amino acid
Von hippel lindau - 3
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Receptor tyrosine kinases - protein phosphatase - takes phosphate off glycogen phosphorylase kinase inactivating it

4. Outside the fibroblast What part of procollagen is cleaved and What is it transformed into
VMA
O- oligosaccharaides
Terminal regions - tropocollagen
Exerts a dominant effect - a heterozygote produces a nonfxnal altered protein that also prevents the normal gene from functioning - mutation of Tx factor its allosteric site - nonfxning mutant can still bind DNA - preventing wild type Tx from binding

5. What is the rate determining enzyme (RDE) of glycolysis
Sucrose = glucose + fructose - lactose = glucose + galactose
Phosphofructokinase 1
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
30 - glycerol -3- phosphate shuttle

6. What is the source of energy in the fasting state between meals
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
PFK - rate limiting enzyme
ATP and alanine
Liver hepatocytes and steroid producing cells of the adrenal cortex

7. What does SAM do
Hypoglycemia
Supply sufficient glucose to brain and RBCs and to preserve protein
X linked frame shif mutation
Transfers methyl units

8. Eukaryotic and prokaryotic DNA synthesis is blank and involves both blank and blank strands
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Semiconservative - continuous and discontinuous strands (okazaki fragments)
SNP
Bone - skin - tendon - dentin - fascia - cornea - late wound repair

9. What neuroanatomical strutures are injured in wernicke - korsakoff
Carnitine acyltransferase I
High output cardiac failure - dilated cardiomyopathy - edema
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Medial dorsal nucleus of thalamus - mamillary bodies

10. Infection with what organism can cause B12 def
2 rings
Diphyllobothrium latum
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
ATP hyrdolysis couple to energetically unfavorable rxns

11. Broadly - What can cause fat - soluble vitamin deficiencies
Malapsorption syndromes like sprue or CF or mineral oil intake
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
ATP hyrdolysis couple to energetically unfavorable rxns
Griseofulvin

12. What kind of branches do glycogen branches have
Alpha 1 -6 and alpha 1 -4
B(1 - 2 - 3 - 5 - 6 - 12) C - biotin and folate (B12 and folate are stored)
L form
Cyclin dependent kinases;constitutive and inactive

13. In a 1000 meter run - Where does energy come from
Same as sprint + OXPHOS
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
After day 1
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

14. What happens in the first stage of collagen synthesis - and Where does it happen
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)
Oxalacetate
Acetyl - CoA carboxylase (ACC)
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin

15. What polar group does guanine have - and what non polar group does thymine have
Ketone - methyl
Oxidized hemoglobin precipiated within RBCs
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
Inc melt - dec fluidity

16. Which kind of osteogenesis imperfecta is fata in utero or in neonatal period
ATP and methionine
Must be both activated and inactivated for cell cycle to progress
Cofactor for LPL
Type II

17. What substance in egg whites binds biotin
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
Avidin
Mediates extra remnant take up
By inhibiting formation of the initiation complex and cause misreading of mRNA

18. What does DNA poly I do?
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Lysine and arginine
CAG - 4
Prokaryotic only - degrades RNA primer and fills in the gap with DNA

19. What are the reactants for glycolysis
Robertsonian translocation and mosaicism
Glucose - 2Pi - 2ADP - 2NAD+
1/4 of offspring from 2 carrier parents are affected - often enzyme def - usually only seen in 1 generation - often more sever than AD - presents in childhood
HVA

20. Where is glucose 6 phosphatase found and What does it do
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)
30 - 50 - 70
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted
In ER - glucose 6- P to glucose

21. What does the TCA cycle produce per 1 acetyl CoA
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
30 - 50 - 70
Fibroblast
Phosphorylation - glycosylation - hydroxylation

22. What happens with dry beriberi
Polyneuritis - symmetrical muscle wasting
RNA poly II
Cleft palate - cardiac abnl - pregs test
CAG

23. How is ammonium transported from muscle to the liver for urea cycle
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Passed to glutamate - then to alanine enters blood - enters liver - coverted to pyruvate and transfers ammonium back to glutamate which gives it to the urea cycle
Antibiotic use or excessive ingestion of raw eggs
Degredation of dietary TG in small intestine

24. What happens at the smooth ER
Neuralgia
Site of steroid synthesis and detoxification of drugs and poisons
TTP
Chylomicrons

25. Which phase of the HMP shunt is reversible and Which is irreversible
G6PD
Oxidative is irreversible
Proline and glycine (non glycosylated forms)
Base + ribose

26. What causes Down syndrome
Mental retardation - flat facies - prominent epicanthal folds - simian crease - gap between 1st 2 toes - duodenal atresia - congenital heart disease (ASD) - inc risk of All and Alzheimers
Acetyl - CoA
ATP and methionine
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21

27. How does cytosine become uracil
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination
Change resulting in early stop codon
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Deamination

28. What is variable expression and What is an example
Leu - lys
Nature and severity of phenotype vary from 1 individual to another - NF type 1
Failure to track objects or develop a social smile
Acetyl - CoA carboxylase (ACC)

29. What is disulfiram used for
Zero
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Nature and severity of phenotype vary from 1 individual to another - NF type 1

30. What are the symptoms of vit A def
Alpha1 antitrypsin
Type II
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Night blindness - dry skin

31. What is the hardy weinberg allele prevalence
Pyroxidine - converted to pyroxidine phosphate a cofactor used in transamination - decarboxylation - glycogen phosphorylase - cystathionine synthesis and heme synthesis - required for synthesis of niacin and tryptophan
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
2 -4 DNP - aspirin
P+q = 1

32. What does acetyl - CoA become before becoming palmitate
Carbomoyl phosphate synthetase I
AR
Lariat shape in order and remove intron precisely and join 2 exons
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)

33. characterize x linked recessive
Prevent strands from reannealing
Sons of heterozygous mothers have 1/2 half chance of being affected - no male to male transmission - and often more severe in males - heterozygous females may be affected
Foliage - small reserve in liver - eat green leaves
Promotor - TATA box - and CAAT box - AT rich

34. What feedback inhibits hexokinase
Glucose -6 phosphate
Stop codon is recognized by release factor - and completed protein is released from ribosome
CarTWOlage
Collagen

35. How do macrolides and clindamycin work
Binds 50S - blocking translocation
B100
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
5' of the incoming nucleotide

36. What is the fxn of vit E
Antioxidant - protects RBCs and membrances from free radical damage
Zero
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Lacks glucose 6 phophatase

37. What is the origin of replication
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Oxidizes substrate
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Particular sequence of DNA where replicatino begins - may be single of multiple

38. What drugs can cause folate def
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Mebendazole/thiabendazole
Phenytoin - MTX - and sulfonamides

39. What activates the pyruvate dehydrogenase complex
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)
Acetly- CoA - CO2 - NADH
Connective tissue
Exercise: inc NAD/NADH - inc ADP - inc Ca

40. What inhibits pyruvate kinase
ATP and alanine
Glutamate
NADH - NADPH - FADH2
Malonyl coa

41. What is the activated carrier for 1 carbon units
Microtuble polymerization defect causing a dec in phagocytosis results in recurrent pyogenic infections - partial albinism - and peripheral neuropathy
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
Infection - free radicals generated by inflammatory response
THFs

42. What is the active form of vit D
1 -25 OH2 D3 = calcitriol
Wernicke - korsakoff - dry and wet beriberi
Glycogen phosphorylase
Assistance of upper extremities to stand up

43. What does Citrate Is Krebs starting substrate for making oxaloacetate
Adenosine to inosine
Citrate - isocitrate - alpha ketoglutarate - succinyl - CoA - succinate - fumarate - malate - oxaleoacetate
Blood - bone marrown - amniotic fluid - placental tissue
Miscarriage - stillbirth - chromosomal imbalance (down - patau)

44. What can excess vit B3 cause
SNP
Facial flushing
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA
Liver - ovaries - seminal vesicles

45. Patients with chronic granulomatous disease are at increased risk of infection From which kind of organisms
Glucose to G-6P - hexokinase and fructose -6P to fructose 1 -6 BP phosphofructokinase -1
Type II
Alanine
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus

46. What apolipoproteins are on chylomicrons
Wernicke - korsakoff - dry and wet beriberi
Glycogen synthase
B48 - AIV - CII - E
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein

47. What lab technique is use to profile gene expression levels of thousands of genes simultaneously to study certain diseases and treatments
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
5' to 3'
Active secretion in lungs and GI - reabsorbs in skin
Microarrays

48. What enzyme adds Cl - to the H202 to makes bleach
NADPH
Sucrose = glucose + fructose - lactose = glucose + galactose
Dopamine beta hydroxylase
Myeloperoxidase

49. What is the results of vit B1 def
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1
They yield only acetyl - CoA equivalents
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
75 to 90 - cloverleaf

50. What amino acid makes up most of the octamer
Phenylketones in urine
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Lysine and arginine
Glycine - aspartate - glutamine