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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 cyclin - CDK complexes
Antioxidant - facilitates iron absorption by keeping iron in the Fe2+ reduced state - necessary for hydroxylation of proline and lysine collagen bridges - necessary for dopamine beta hydroxylase which converts DA to NE
Poly A polymerase - signal is AAUAA
Must be both activated and inactivated for cell cycle to progress
Kidney - ears - eyes

2. In which structures do you find microtubules
Terminal regions - tropocollagen
Initiate chains
Flagella - cilia - mitotic spindles
Prokaryotic only - degrades RNA primer and fills in the gap with DNA

3. What is the Name and function of vit B1
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Stop codon is recognized by release factor - and completed protein is released from ribosome
Hurlers syndrome - alpha L iduronidase - heparan sulfate/dermatan sulfate - AR

4. Do balanced translocations cause abnl phenotype
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Proline and lysine - vit C
No
HDL

5. What does desmin stain for
Muscle
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
NF2 on chromosome 22
Hereditary hemorrhagic telangiectasia (Osler - Weber - Rendu syndrome)

6. What is the Name and fxn of vit B5
Purines= A - G pyrimidine = C - T (U)
Cystine kidney stones - cystine staghorn calculi - cystine is made of two cysteines connected by disulfide bond
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase

7. Describe robertsonian translocation
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
AMP - fructose 2 -6 BP
TRNA
Anabolic processes as a supply of reducing equivalents

8. What kind of RNA is transported out of the nucleus
Reticulin - skin - blood vessels - uterus - fetal tissue - granulation tissue
Niacin - constituent of NAD and NADP - derived from tryptophan
Transfers methyl units
Only processed RNA

9. phosphorylation of glucose to yield glucose 6 phosphate serves as the 1st step of what rxns and what enzymes catalyze it
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Ketone - methyl
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
Inhibits acetaldehyde dehydrogenase and contributes to hangover symptoms

10. What catacholamine step is SAM required for
APRT + PRPP
Unwinds DNA template at replcation fork
Lacks glucose 6 phophatase
Conversion of NE to epi

11. What are pyrimidines made from
Orotate precursor - with PRPP added later
UDP glucose pyrophosphorylase
Acetly- CoA - CO2 - NADH
1 ring

12. What tissues have only aldose reductase
AMP - fructose 2 -6 BP
Infection - free radicals generated by inflammatory response
Malapsorption syndromes like sprue or CF or mineral oil intake
Schwann cells - lens - retina - kidneys

13. Where do you find elastin and What does it do
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
Hepatic glycogenolysis >> hepatic gluconeogenesis > adipose release of FFA
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
HDL

14. ADPKD is associated with What additional conditions
Lungs - large arteries - elastic ligaments - vocal cords - ligamenta flava - stretch.
Polycystic liver disease - berry aneurysm - mitral valve prolapse
Metachromatic leukodystrophy - arylsulfatase A - cerebroside sulfate AR
Acetly- CoA - CO2 - NADH

15. What is uniparental disomy
Breaks down acyl - coa to acetyl coa groups in mito
Offspring receives 2 copies of a chromosome from 1 parent and no copies from the other parent
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
Only processed RNA

16. Pts with albinism are at inc risk For what cancer
Alpha 1 -4 glucosidase
Skin
Basement membrane or basal lamina
Specific glycosylases - AP endonuclease

17. What is sorbitol - how and why is it made
Ribos first then deoxyribos with ribonucleotide reductase
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
Liver and leafy veggies
Alcohol version of glucose - can trap glucose in cell - aldose reductase

18. What does a phosphorylase do
Adds an inorganic phosphate onto substrate without using ATP
Result from phagocytic removal of heinz bodies my macs - G6PD def
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles
Excess NADH shunts oxaloacetate to malate (backwards) stalling the TCA and shunting glucose and FFA to ketone body production

19. What are the clinical features of I cell diesase
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Never go to G0 - divide rapidly with a short G1 - bone marrow - gut epi - skin - hair follicles
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies

20. What are the reactants for glycolysis
Glucose - 2Pi - 2ADP - 2NAD+
Anchor muscle fibers - primarily in skeletal and cardiac muscle
Degredation of dietary TG in small intestine
Specific glycosylases - AP endonuclease

21. Where is glucokinase found - What are the Km and Vmax - and what induces it
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
DTMP
Liver and beta cells of pancreas - low affinity - high Km - high capacity - high Vmax - induced by insulin

22. What neuroanatomical strutures are injured in wernicke - korsakoff
Mediates chylomicron secretion
Medial dorsal nucleus of thalamus - mamillary bodies
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Krabbes - galactocerebrosidase - galactocerebroside - AR

23. What happens in vit D excess
Hydroxyurea - inhibits ribonucleotide reductase - 6 MP - blocks de novo purine synthesis - 5 FU inhibits thymidilate synthase - MTX - inhibits DHFR - Trimethroprin inhibits bacterial DHFR
Mucus secreting globlet cells and antibody secreting plasma cells
Hypercalciuria - loss of appetite - stupor - seen in sarcoidosis from activation fo vit D by epithelioid macrophage
Zero

24. What is NAD+ generally used for
Dermatitis - enteritis - alopecia - adrenal insuff
Malonyl coa (+ biotin= palmitiate - 1 16C fatty acid)
Dopamine beta hydroxylase
Catabolic processes to carry reducing equivalents away as NADH

25. What inhibits pyruvate kinase
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Inhibits 50S peptidyltransferase
ATP and alanine
Met - val - arg his

26. What is the defect in II A familial hypercholesterolemia
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles
AD absent of dec LDL receptors causes accelerated atherosclerosis - achilles xanthomas and corneal arcus - increase LDL and elecated cholesterol
African Americans and Asians
Creat a nick in the helix to relieave supercoils created during replication

27. What is variable expression and What is an example
Oxidative and nonoxidative - no ATP produced or used
Coarse facial features - clouded corneas - restricted joint movements - high plasma levels of lysosomal enzymes - often fatal in childhood
Genetic code is conserved throughout evolution - except for mito - archaebacteria - mycoplasma - and some yeast
Nature and severity of phenotype vary from 1 individual to another - NF type 1

28. spheroid RBCs due to spectrin or ankyrin defect - hemolytic anemia - inc MHCH - splenectomy is curative
Lactate
Hereditary spherocytosis
Base + ribose + phosphate (3' -5') phosphodiester bond
Lariat shape in order and remove intron precisely and join 2 exons

29. What are the findings in Down's 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
Phosphorylation - glycosylation - hydroxylation
Malate - aspartate shuttle or the glycerol 3 phosphate shuttle
African Americans and Asians

30. What rxn creates ATP
Excess ATP - dATP - feeback inhibits ribonucleotide reductase - no DNA synthesis
Phosphenolpyruvate to pyruvate catalyzed by pyruvate kinase
TRNA
Pseudomonas and s aureus

31. What are uncoupling agents
HDL
Liver - ovaries - seminal vesicles
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
Lack of proper dietary therapy during pregnancy leading to microcephaly - mental retardation growth retardation - congenital heart defects

32. colon becomes covered witih adenomatous polyps after puberty - progresses to colon cancer unless resected
Reads usual codon but inserts wrong AA
Acetyl - CoA to malonyl - CoA (2C to 3C)
FAP
TRNA

33. Gene imprinting implies that How many alleles are active at a single locus
X- linked recessive
Neg to pos
Glycogen and FFA oxidation; glucose conserved for final sprinting
One

34. Which aspect of the spliceosome do patients with lupus make antibodies against
Lariat shape in order and remove intron precisely and join 2 exons
N to C
Inhibits lipoic acid - vomiting - rice water stools - garlic breath
SnRNPs

35. Type IV BM
Inc dicarboxylic acids - dec in glucose and ketones
4 under the floor
Flank pain - hematuria - HTN - progressive renal failure
CAG - 4

36. How is Lesch Neyhan inherited
X- linked recessive
II - VII - IX - X (1972) protein C and S
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Athralgias - fatigue - headaches - skin changes - sore throat - alopecia

37. What is the activated carrier for Acyl
ATP - citrate
Dermatitis - alopecia - enteritis
Constitutive - random insertion of gene into mouse genome and conditional - targeted insertion or deletion of gene through homologous recombination with mouse gene
Coenzyme A - lipoamide

38. What induces pyruvate kinase
F16BP
Transmitted only through mother - all offspring of affected females may show signs of disease
HMG- CoA - brain to 2 molecules of acetyl - Coa - excreted in urine
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia

39. What substances induce phosphofructokinase
Microarrays
Each codon specifies only 1 amino acid
Depleted for gluconeogenesis staling the TCA cycle and shunting glucose and FFA to production of ketone bodies
AMP - fructose 2 -6 BP

40. What lab technique is use to profile gene expression levels of thousands of genes simultaneously to study certain diseases and treatments
Von Gierke's - Pompe - Cori - McArdle
Microarrays
More than 1 codon may code for the same amino acid
L form

41. Which part of the DNA binds RNA polymerase and multiple other TFs upstream from gene locus
Familial hypercholesterolemia - hyperlipidemia type IIA
Arg and his inc in histones Which bind negatively charged DNA
Promotor - TATA box - and CAAT box - AT rich
Production of a recombinant DNA molecule that is self perpetuating - plasmids - selection - restriction enzyme cleavage - tissue mRNA with reverse transcriptase to make cDNA

42. characterize autosomal recessive inheritance
Loss of brush border enzyme causing bloating - cramps - osmotic diarrhea
EtOH dehydrogenase and acetaldehyde dehydrogenase
High output cardiac failure - dilated cardiomyopathy - edema
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

43. Type I bone
Kwashiorkor - small child with swollen belly
Dec methionine - inc cystiene - inc B12/folate
Transfers cholesterol from mature HDL to VLDL - IDL and LDL (cholesterol ester transfer protein)
BOne

44. What creates the musty body odor in PKU
Von gierkes - glucose 6 phosphatase
Disorder of aromatic amino acid metabolism
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Robertsonian translocation and mosaicism

45. How do you diagnose CFTR
CGG
Inc Cl - in sweat
Nonsense > missense > silent
RER - translation of alpha chains - usually Gly-X-Y polypeptide (preprocollagen)

46. Which cells are rich in smooth ER
Thiamine - in thiamine pyrophosphate a cofactor for pyruvate dehydrogenase (glycolysis) - alpha ketoglutarate dehydrogenase (TCA cycle) - transketolase (HMP shunt) - and branched - chain AA dehydrogenase
Autosomal recessive diseases
Liver hepatocytes and steroid producing cells of the adrenal cortex
Wobble

47. metaphse chromosomes are stained - ordered and numbered according to morphology - size - arm length ratio - banding pattern
Inc melt - dec fluidity
Karyotyping
1- capping on 5' (7- methyguanosine) 2 - polyadenylation on 3' end 3 - splicing out of introns
Inc Cl - in sweat

48. How do glucagon/epi lead to glycogenolysis
Fabrys - alpha galactosidase A - ceramide trihexoside - XR
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis
Change resulting in early stop codon
Glucose 6P to CO2 - 2NADPH - ribulose 5P - G6PD - rate limiting step

49. What does vit E def cause
APC on chromosome 5
Inc vit B6
Vincritsine/vinblastine
Inc fragility of RBC - hemolytic anemia - muscle weakness - posterior column and spinocerebellar tract demyelination

50. What is pleiotropy and given an example
1 kind with multiple subunits
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Robertsonian translocation and mosaicism
9+2 arrangement of microtubules