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Biochemistry

Instructions:

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. What substances are uncouling agents
Cofactor for LPL
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
2 -4 DNP - aspirin
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

2. In what cell is collagen synthesis initiated
Wobble
Active secretion in lungs and GI - reabsorbs in skin
Fibroblast
Prevent strands from reannealing

3. What are the physical findings of fragile x syndrome
By inhibiting formation of the initiation complex and cause misreading of mRNA
Exons
Mental retardation - macro - orchidism - long face with large jaw - large everted ears - autism - and mitral valve prolapse
Cartilage - hyaline - vitreous body - nucleus pulposus

4. What converts dopamine to NE
DNA
Anabolic processes as a supply of reducing equivalents
Dopamine beta hydroxylase
2pq

5. How do odd chain fatty acids participate in gluconeogenesis
SnRNPs and other proteins
Antibiotic use or excessive ingestion of raw eggs
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects
Via 1 proprionyl - CoA which can enter the TCA as succinyl - CoA and undergo gluconeogenesis

6. What apolipoproteins are on chylomicrons
B48 - AIV - CII - E
APRT + PRPP
Neurons
Glutamate

7. What does a phosphatase do
Same AA - often base change in 3rd position of codon (tRNA wobble)
Removes phosphate group from substrate
NAD+
Common metabolites like pyruvate and acetyl CoA and excess NH4+ converted to urea and exreted

8. What two proteins make up microtubules and how are they arranged
They yield only acetyl - CoA equivalents
Inhibits RNA polymerase II - found in death cap mushrooms
Cofactor for LPL
Alpha and beta tubulin - dimers have two GTP bound

9. What is the Name and fxn of vit B12
Williams syndrome
Cobalamin - cofactor of homocysteine and methyltransferase - methylmalonyl CoA mutase
Superoxide dismutase
Debranching enzyme

10. How does ouabain work
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Base + ribose
Alpha 1 -4 glucosidase
Inhibits the Na/K pump by binding the K side

11. What does osteogenesis imperfecta causes and why
Ribose 5- P to PRPP
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
SnRNPs
1 ring

12. what disease can cause pellagra
Oxidative is irreversible
Autosomal recessive diseases
Lactate
Hartnup disease - dec tryptophan absoprtion - malignant carcinoid syndrome (inc tryptopha metabolism) and INH (dec vit B6)

13. What happens on the nonoxidative arm of the HMP shunt and What is the key enzyme and cofactor
Pyruvate to oxaloacetate (3C to 4C)
Protein kinase A
Base + ribose
Ribulose 5P to ribose 5P - G3P and F6P - transketolase and B1

14. What does DNA ligase do
Depletes alpha - ketoglutarate leading to inhibition of TCA cycle - tremor slurring of speech - somnolence - vomiting - cerebral edema - blurring of vision
Disease
Seals.
Debranching enzyme

15. What is a silent mutation
THFs
Rb and p53
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms
Same AA - often base change in 3rd position of codon (tRNA wobble)

16. Where does gluconeogenesis primarily happen and What are other sites where the enzymes are located
Tyrosine
Cytosol
Liver - also in kidney and gut epithelium
Inc permeability of membrane causing a dec in proton gradient and inc in O2 consumption - ATP synthesis stops - but electron transport continues to produce heat

17. What is the main source of folate
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Nissl body - enzyme and NTs
Inhibit DNA gyrase specific for prokaryotic topoisomerase
Foliage - small reserve in liver - eat green leaves

18. What does helicase do
Unwinds DNA template at replcation fork
Rickets in kids - bending bones - osteomalacia in adults - hypocalcemia tetany - breast milk has dec vit D (supplement in dark skinned patients)
Polyneuritis - symmetrical muscle wasting
Alpha 1 -6 and alpha 1 -4

19. metaphse chromosomes are stained - ordered and numbered according to morphology - size - arm length ratio - banding pattern
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Karyotyping
Makes RNA primer on which DNA poly III can initiate replication
GAA

20. How doe NADH electrons from glycolysis and the TCA cycle enter the mitochondiria
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
Not all individuals with a mutant genotype show the mutant phenotype
Orotic acid phosphoribosyltransferase or orotidine 5'- phosphate decarboxylase
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin

21. cytoskeletal elements in micorvilli - muscle contracting fibers - cytokenesis - adherens jxns
Initiate chains
Aberrant 3rd and 4th branchial arches causing 22q11 deletion - cleft palate - abnl facies - thymic dysplasia - cardiac defects - hypocalcemia secondary to parathyroid aplasia
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Actin and myosin

22. In base excision repaire - what recognizes and removes damaged bases and what cuts the DNA to remove the empty sugar
Acetoacetate and beta hydroxybutyrate
Promotor - TATA box - and CAAT box - AT rich
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
Specific glycosylases - AP endonuclease

23. What is the Name and function of vit B2
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Tryptophan
Glycogen and FFA oxidation; glucose conserved for final sprinting
Alpha - ketoglutarate dehydrogenase complex

24. How does ethanol induce hypoglycemia
HMP shunt
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
Methionine encode by only 1 codon (AUG)
Mucus secreting globlet cells and antibody secreting plasma cells

25. What is NADPH used for
Hepatic glycogenolysis - adipose tissue release of FFA - muslce and liver FFA - hepatic gluconeogenesis from peripheral tissue lactate and alanine and from adipose tissue glycerol and proprionyl - coA (odd chain FFA)
Anabolic processes as a supply of reducing equivalents
III - joint dislocation - anuerysms - organ rupture
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints

26. What happens with dry beriberi
II - VII - IX - X (1972) protein C and S
Polyneuritis - symmetrical muscle wasting
Unmethylated - newly synthesized - HNPCC
Cleft palate - cardiac abnl - pregs test

27. What is made fir rNucleotides or deoxyrNucleotides and what enzyme is necessary to convert one to the next
5' of the incoming nucleotide
Ribos first then deoxyribos with ribonucleotide reductase
Degredation of TG circulating in chylomicrons and VLDLs
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)

28. What are the glucogenic/ketogenic amino acids
Ile - phe - thr - trp
Dec methionine - inc cystiene - inc B12/folate
N- acteylcysteine - cleave disulfide bonds within mucus glycoproteins
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue

29. Which enzyme involved in RNA synthesis does not require a template
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais
Poly A polymerase - signal is AAUAA
IMP precursor
Inhibits EtOH dehydrogenase and is an antidote for methanol and ethylene glycol poisoning

30. What are the findings with homocystinuria and What amino acid is needs to be supplemented
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Homocystein in ruine - mental retardation - osteoporosis - tall stature - kyphosis - lens subluxation and atherosclerosis leading to stroke and MI - cysteine
RNA
CG- 3 > AT-2 - More CG content - melting point goes up

31. Which part of the DNA binds RNA polymerase and multiple other TFs upstream from gene locus
Faulty collagen synthesis - hyperextensible skin - tendency to bleed - easy bruising - hypermobile joints
Promotor - TATA box - and CAAT box - AT rich
Specific glycosylases - AP endonuclease
Purines= A - G pyrimidine = C - T (U)

32. Which direction does dynein go
Covalent cross - linking by lysyl oxidase to make collagen fibrils
Silencers
Post to neg
Aldolase B - AR - fructose 1P accumulates causing a dec in availabel phosphate which inhibts glycogenolysis and gluconeogenesis leading to hypoglycemia - cirrhosis - jaundice and vomiting

33. What components come together to make S- adenosyl methionine
Initiate chains
Makes RNA primer on which DNA poly III can initiate replication
ATP and methionine
III - joint dislocation - anuerysms - organ rupture

34. Name as many x- linked recessive disorders as you can

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35. What is imprinting and give an example

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36. What is the result of vit B5 def
The triphosphate bond
Early in life - AR - inability to synthesize lipoproteins due to def in apoB100 and B48 - intestinal biopsy shows accumulation within enterocytes due to inability to export absorbed lipid as chylomicrons - failure to thrive - steatorrhea - acanthocyt
Base + ribose
Convulsions - hyperirritability - peripheral neuropathy - deficiency inducible by INH and oral contraceptives - sideroblastic anemais

37. What is the breakdown product of NE
Familial hypercholesterolemia - hyperlipidemia type IIA
VMA
RER
EtOH dehydrogenase and acetaldehyde dehydrogenase

38. What two cells are particularly rich in RER
Glucose - 2Pi - 2ADP - 2NAD+
Acetyl - CoA to malonyl - CoA (2C to 3C)
Mucus secreting globlet cells and antibody secreting plasma cells
Mutations at different loci can produce the same phenotype - marfans - MEN 2B - homocystinuria; all cause marfinoid habitus - also albinism

39. What are the 2 distinct phases of the HMP shunt and How many ATP are used and produced
Glycogen and FFA oxidation; glucose conserved for final sprinting
Debranching enzyme
Oxidative and nonoxidative - no ATP produced or used
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis

40. What is the RDE of glycogenolysis
Glycogen phosphorylase
Microarrays
Failure to track objects or develop a social smile
Wernicke - korsakoff - dry and wet beriberi

41. What causes Marfan syndrome
Lack of tyrosinase (no melanin) AR ordefective tyrosine transporters (less tyrosine) - can results in lack of migration of NC cells
ATP - citrate
Sulfation
Defect in fibrillin

42. What is NADPH's role inside RBCs
F16BP
Huntingtons
Keep glutathione reduced so it can detoxify free radicals and peroxides
Defect in fibrillin

43. characterize mitochondrial inheritance
MRNA
Stored ATP - creatine phosphate - anaerobic glycolysis
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Transmitted only through mother - all offspring of affected females may show signs of disease

44. What is the RER called in neurons and What is made there
CarTWOlage
Nissl body - enzyme and NTs
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
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA

45. How is Lesch Neyhan inherited
Huntingtons
X- linked recessive
Sulfation
One

46. What is the Hardy Weinberg disease prevalence equation
P2 +2pq+ = 1
D2 = ergocalciferol - ingested from plants D3 = cholecalciferol - ingested from milk - formed in sun exposed skin
Coenzyme A - lipoamide
Epithelial cells

47. Pts with albinism are at inc risk For what cancer
HMG- CoA synthase
Skin
By inhibiting formation of the initiation complex and cause misreading of mRNA
Flagella - cilia - mitotic spindles

48. Where do you find elastin and What does it do
Octamer = 2 sets of H2A - H2B - H3 - H4 - tie =H1
Terminal regions - tropocollagen
Inc CPK and muscle biopsy
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.

49. What does universal genetic code refer to and What are some exception
Cystic medial necrosis of aorta leading to aortic incompetence and dissecting aortic aneurysms - floppy mitral valve - subluxation of lenses
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Initiate chains
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase

50. cytoskeletal elements associated with cilia - flagella - mitotic spindle - neurones and centrioles
ATP and methionine
Microtubules
Read from a fixed starting point as a continuous sequence of bases
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis