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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 does the passage of electrons result in that when coupled to OXPHOS drives the production of ATP
NF2 on chromosome 22
Proton gradient
Adenosine to inosine
Malabsorption and steatorrhea (ADEK)

2. What does beta oxidation do and Where does it occur
Pyrophosphate (B1 - thiamine - TPP) FAD (B2 - riboflavin) - NAD (B3 - niacin) - CoA (B5 pantothenate) - lipoic acid
Degradation of TG stored in adipocytes
Initiate chains
Breaks down acyl - coa to acetyl coa groups in mito

3. What catacholamine step is SAM required for
Gaucher's - beta glucocerebrosidase - glucocerebrosie - AR
Oxalacetate
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Conversion of NE to epi

4. What liberates glucose from glucose 6 P
Phosphofructokinase 1
Glucose 6 phosphatase
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Sulfation

5. What is the activated carrier for phosphoryl
ATP
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
III - joint dislocation - anuerysms - organ rupture
Tyrosine

6. Where is EtOH dehydrogenase located
Neuralgia
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
4 under the floor
Cytosol

7. Where is glucose 6 phosphatase found and What does it do
In ER - glucose 6- P to glucose
II - VII - IX - X (1972) protein C and S
Mutated dystrophin gene - less severe - adolescence
Muscle

8. Which enzyme involved in RNA synthesis does not require a template
Inability to transport LCFAs into mitochondria results in toxic accumulation causing weakness - hypotonia - hyperketotic hyperglycemia
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
Poly A polymerase - signal is AAUAA
Inhibits 50S peptidyltransferase

9. What enzyme degrades a small amount of glycogen in lysosomes
HMG- CoA (HMG- CoA to mevalonate
GTP
B-100 - CII and E
Alpha 1 -4 glucosidase

10. How many ATP are created by aerobic metabolism of glucose in the heart and liver via what shuttle
N to C
Backup of substrate (pyruvate and alanine) resulting in lactic acidosis - congenital or acquired from thiamine def in EtOH - neuro defects
32 - malate aspartate shuttle
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine

11. What does a decrease in decrease in NADPH lead to and why
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
Poor defense from oxidizing agents - fava beans - sulfonamides - primaquine - antituberclosis drugs leadig to hemolytic anemia.
Neurofibromatosis type 1 (von Recklinghausens disease)
Scrutinizes - hydrolyzes the bond

12. hepatosplenomegaly - aseptic necrosis of femur - bone crisis - MACS that look like crumpled tissue paper

13. When are glycogen reserves depleted
FAP
SAM
Directly inhibit the Na/K pump which leads to indirect inhibition of Na/Ca exchange - inc calcium inside the cell - inc cardiac contractility
After day 1

14. What is anticipation and give an example
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
Failure to track objects or develop a social smile
Severity of disease worsens or age of onset of disease is earlier in succeeding generations - huntingtons
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

15. What does pancreatic lipase do
AR
PMNs
Degredation of dietary TG in small intestine
Oxidative and nonoxidative - no ATP produced or used

16. What can excess vit B3 cause
Removes phosphate group from substrate
Oxidative is irreversible
Facial flushing
Flagella - cilia - mitotic spindles

17. What are the results of unbalanced translocation
Phosphorylation - glycosylation - hydroxylation
Glycine
CO2 + NH4 needs carbamoyl phosphate synthase I - in the mitochondria
Miscarriage - stillbirth - chromosomal imbalance (down - patau)

18. What rxn does propionyl - CoA carboxylase catalyze
Propionyl - CoA to methylmalonyl - CoA (3C to 4C)
Cre - lox system
Pompe's lysosomal alpha 1 -4 glucosidase (acid maltase) (pompe trashes the pump; heart - liver - muscle)
UGA - UAA and UAG

19. What produces NADPH
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
HMP shunt
Essential for the activity of over 100+ enzymes - important in the formatio of zinc fingers -
Site of steroid synthesis and detoxification of drugs and poisons

20. Where are cytosolic and organellar proteins made
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Change resulting in misreading of all nucleotides downstream - usually resulting in a truncated nonfxnal protein
Free ribosomes
Cheilosis - inflammation of lips - scaling and fissures at the corner of the mouth - corneal vascularization

21. What substance in egg whites binds biotin
ATP hyrdolysis couple to energetically unfavorable rxns
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
Avidin
Infection - free radicals generated by inflammatory response

22. What is the order of severity for the different types of mutations
Cartilage - hyaline - vitreous body - nucleus pulposus
Rb and p53
Nonsense > missense > silent
Miscarriage - stillbirth - chromosomal imbalance (down - patau)

23. What lab value can distinguish orotic aciduria from ornithine transcarbamoylase def?
In cytosol - oxaloacetate to phosphenolpyruvate - requires GTP
Anchor muscle fibers - primarily in skeletal and cardiac muscle
OTC has hyperammonemia - orotic aciduira does not
Fasting

24. Where do you find elastin and What does it do
GAA
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
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
FAP

25. Of the four possible fates for pyruvate - which ends anaerobic glycolysis as in RBCs - leukocytes - kidney medulla - lens - testes and cornea
Cytosol - F 1 -6 BP to fructose 6 Phosphate
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT
Lactate
Failure to track objects or develop a social smile

26. What is the defect in cystinuria
Mediates extra remnant take up
Von hippel lindau - 3
Heterochromatin = HighlyCondensed
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT

27. What two pathways is carbomoyl phosphate involved in - and what enzyme deficiency leads to a build of carbamoyl phosphate leading to what element in pyrimidine synthesis
Tuberous sclerosis
De novo pyrimidine synthesis and urea - ornithine transcarbamoyl def in the urea cycle leads to a build of CP - then converted to orotic acid in pyrimidine synthesis pathway
Hypoxanthine to xanthing and xanthine to uric acid
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin

28. What collagen type is most frequently affected in ehlers danlos and What are common complications
Neural tube
Anabolic processes like steroid and fatty acid synthesis - respiratory burst - P-450 - glutathione reductase
CAG
III - joint dislocation - anuerysms - organ rupture

29. What drugs can cause folate def
5' to 3'
Skin
Phenytoin - MTX - and sulfonamides
Hepatic overproduction of VLDL causing pancreatitis - elvelated TGs and VLDL

30. What is the exception to genetic redundancy
Inc glucagon - inc cAMP - inc PKA
Palate - facial and cardiac defects
Methionine encode by only 1 codon (AUG)
VLDL

31. What is Retin A used topically for
Wrinkles and acne
O- oligosaccharaides
EtOH dehydrogenase and acetaldehyde dehydrogenase
Y shaped region along the DNA template where leading nad lagging strands are synthesized

32. What does inc phenylalanine lead to...
After day 1
Orotate precursor - with PRPP added later
Active secretion in lungs and GI - reabsorbs in skin
Phenylketones in urine

33. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
Glucose 6 phosphate dehydrogenase (G6PD)
Actin and myosin
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Phosphorylation - glycosylation - hydroxylation

34. What is the Name and function of vit B2
Progressive hreditary nephritis and deafness - associated with occular disturbances - due to abnl type IV collagen - usually x- linked recessive
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia
Silencers

35. What does the vimentin stain for
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Cyclin dependent kinases;constitutive and inactive
Flagella - cilia - mitotic spindles
Connective tissue

36. cell signaling defect of fibroblast growth factor (FGF) receptor 3 - results in dwarfism - short limbs - head/trunk nl size - associated with advanced paternal age
Achondroplasia
Unwinds DNA template at replcation fork
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)

37. What enzyme adds Cl - to the H202 to makes bleach
Myeloperoxidase
Acetoacetate and beta hydroxybutyrate
Autosomal recessive diseases
Hereditary defect of renal tubular amino acid transporter for cystein - ornithine - lysine and arginine in PCT

38. What metabolic rxns occur in the mitochondria
FISH
Fatty acid oxidation - acetyl - Coa production - TCA cycle - OXPHOS
Sever atherosclerotic disease early in life - and tendon xanthomas on the achilles - MI may develop before 20
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

39. In which state is PFK-2 active
Ile - phe - thr - trp
Fed
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects

40. How do microtubules grow and collapse
Prokaryotic only - degrades RNA primer and fills in the gap with DNA
Grows slowly - collapses quickly
RRNA
CG- 3 > AT-2 - More CG content - melting point goes up

41. What occurs to oxaloacetate in starvation and DKA
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
Cyclin dependent kinases;constitutive and inactive
F16BP
Blood - bone marrown - amniotic fluid - placental tissue

42. Type IV collagen is an important structural componenet of the BM for which 3 organs
Liver - ovaries - seminal vesicles
THFs
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Kidney - ears - eyes

43. What is the most abundant type of RNA
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Breaks down acyl - coa to acetyl coa groups in mito
Lysine and leucine
RRNA

44. Type IV collagen
Hyperlipidemia
Basement membrane or basal lamina
Night blindness - dry skin
II - VII - IX - X (1972) protein C and S

45. What does vit C def cause
TTP
Rb and p53
Scurvy - swollen gums - bruising - hemarthrosis - anemia - poor wound healing - weakened immune response
Procollagen - triple helix of 3 alpha collagen chains

46. How is ammonium transported from muscle to the liver for urea cycle
Ketone - methyl
The triphosphate bond
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
Krabbes - galactocerebrosidase - galactocerebroside - AR

47. What is the hardy weinberg allele prevalence
TRNA
SNP
Skin
P+q = 1

48. What is the RER called in neurons and What is made there
Nissl body - enzyme and NTs
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)
Creat a nick in the helix to relieave supercoils created during replication
Phenylalanine

49. What are the fetal screening measures for Down
Heterochromatin = HighlyCondensed
DNA
Dec AFP - inc betahCGH - dec estradiol - inc inhibin - inc nuchal translucency on US
Site of steroid synthesis and detoxification of drugs and poisons

50. What initiates protein synthesis
GTP hydrolysis - initiation factors assemble 40S ribosomal subunit with initiator tRNA and are released with mRNA and ribosomal subunit assemble with the complex
Plasma membrane - 3Na out - 2K in - ATP on cytoplasmic side
VLDL
Gamma carboxylation of glutamic acid residues on various proteins concerned with blood clotting - synthesized in intestinal flora