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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 is the RER called in neurons and What is made there
Pyruvate - NAD+ - CoA
B6
Nissl body - enzyme and NTs
Phenylalanine hydroxylase

2. In which state is PFK-2 active
Ribose 5- P to PRPP
Fed
Tendency for certain alleles at 2 linked loci to occur together more often than expected by chance - varies is different populations
Consesus sequenec of base pairs

3. Is there any requirement for homology in NHEJ
Fasting
Nature and severity of phenotype vary from 1 individual to another - NF type 1
No - its non homologous
Not all individuals with a mutant genotype show the mutant phenotype

4. The golgi apparatus fxns as a distribution center between what organelles in the cell and What does it process
Hyperlipidemia
Marfans
SnRNPs and other proteins
For proteins and lipids from ER to plasma membrane - lysosomes and secretory vesicles

5. spheroid RBCs due to spectrin or ankyrin defect - hemolytic anemia - inc MHCH - splenectomy is curative
Oxidative and nonoxidative - no ATP produced or used
Muscle
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
Hereditary spherocytosis

6. What are CDKs
Cyclin dependent kinases;constitutive and inactive
Neurons
Protective against malaria
Attachment of ubiquitin to defective proteins tag them for breakdown

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

8. What is the breakdown product of dopamine
AR
HVA
Modifies N- oligosaccharides
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light

9. How is vit D stored
Heme synthesis - urea cycle and gluconeogenesis - HUGs take two
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
Presence of both nl and mutated mtDNA resulting in mitochondrial inherited disease
25OHD3

10. Where is hexokinase found - What is its Km and Vmax and what uninduces it
Autosomal recessive diseases
Phenylalanine
Ubiquitous - low Km - high affinity - low capacity low Vmax - uninduced by insulin
75 to 90 - cloverleaf

11. What is the energy source for tRNA actication (charging)
Breaks down acyl - coa to acetyl coa groups in mito
ATP
Lebers hereditary optic neuropathy - degeneration of retinal ganglion cells and axons - leads to acute loss of central vision. Mitochondrial myopathies
Attachment of ubiquitin to defective proteins tag them for breakdown

12. What does the golgi add to serine and threonine residues
O- oligosaccharaides
Glycolysis and aerobic respiration
Animal products - synthesized only by microorganisms - large reserve pool - mainly in liver
40 - 60 - 80

13. What happens with dry beriberi
Polyneuritis - symmetrical muscle wasting
Unwinds DNA template at replcation fork
Wernicke - korsakoff - dry and wet beriberi
Glycogen synthase

14. What is proteasomal degredation
MEN - 2A and 2B with ret gene
Attachment of ubiquitin to defective proteins tag them for breakdown
Oral uridine administration
Nature and severity of phenotype vary from 1 individual to another - NF type 1

15. Type II cartilage
Y shaped region along the DNA template where leading nad lagging strands are synthesized
Mediates extra remnant take up
Specific glycosylases - AP endonuclease
CarTWOlage

16. Where are FADH2 electrons transferred to...
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
Comlex II
Acetly- CoA - CO2 - NADH
B100 and E

17. What is the wernicke - korsakoff clinical picture
Hypoxanthine to xanthing and xanthine to uric acid
African Americans and Asians
Confusion - opthalmoplegia - ataxia - confabulation - personality changes and memory loss
5' of the incoming nucleotide

18. characterize mitochondrial inheritance
Transmitted only through mother - all offspring of affected females may show signs of disease
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Pyruvate carboxylase - PEP carboxykinase - fructose 1 -6 biphosphatase - glucose 6 phosphatase
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes

19. What defects characterize DiGeorge syndrome
Binds 50S - blocking translocation
Phenytoin - MTX - and sulfonamides
Thymic - parathyroid and cardiac
Inhibit DNA gyrase specific for prokaryotic topoisomerase

20. What are covalent alterations
Mediates chylomicron secretion
Phosphorylation - glycosylation - hydroxylation
B100
Unwinds DNA template at replcation fork

21. For eukaryotes - Where does replication begin?
Blood - bone marrown - amniotic fluid - placental tissue
Degradation of TG remaining in IDL
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)
Consesus sequenec of base pairs

22. Which step in the de novo purine and pyrimidine synthesis pathway requires just aspartate
Base + ribose + phosphate (3' -5') phosphodiester bond
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Trisomy 18 - severe mental retardation - rocker bottom feet - micrognathia - low set ears - clenched hands - prominent occiput - congenital heart disease - death usually within the first year
Orotic acid to UMP

23. What are the fat soluble vitamins and What does their absorption depend on...
Stored and undergoes glycogenolysis to maintain blood sugar at appropriate levels
ADEK - dependent on gut (ileum) and pancreas - accumulate in fat and can cause toxicity
Provide a source of NADPH from an abundantly available glucose 6P - create ribose for nucleotide synthesis and glycolytic intermediates
Procollagen - triple helix of 3 alpha collagen chains

24. What are the products for glycolysis
IMP precursor
2 pyruvate - 2ATP - 2NADH - 2H+ - 2H2O
Krabbes - galactocerebrosidase - galactocerebroside - AR
Nucleotide excision repair - xeroderma pigmentosum; unable to repair thymidine dimers caused by UV light

25. What apolipoprotiens are on VLDL
Semiconservative - continuous and discontinuous strands (okazaki fragments)
B-100 - CII and E
Leu - lys
30 - 50 - 70

26. Of the four possible fates for pyruvate - which one carries amino groups to liver from muscle
Alanine
Arginine
Macrocytic - megaloblastic anemia - hypersegmented PMNs - neurologic symptoms - (parasthesias - subacute combined degeneration) due to abnl myelin - prolonged becomes irreversible
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

27. Type I bone
Hunters - iduronate sulfatase - heparan sulfate/dermatan sulfate - XR
BOne
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
Degredation of TG circulating in chylomicrons and VLDLs

28. What are the functinos of vitamin A
Transmitted through both parents - affected mother may have affected children - affected father will have affected children
Changed AA (convservative - new AA is similar in chemical structure)
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
Antioxidant - constituent of visual pigment - essential for nl differntiation of epithelial cells into specialized tissue (pancreatic cells - mucus secreting cells) used to treat measles

29. Which are the basic amino acids
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Cyclin dependent kinases;constitutive and inactive
Neither of 2 alleles is dominant - blood groups
Arg - lys - his - arg is most basic - has has no charge at body pH

30. What does apoA 1 do
Activates LCAT
Regulatory proteins that control cell cycle events; phase specific; activate CDKs
Catalase positive (catalase neg produce H2O2 the cell can use) like S. aureus or aspergillus
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21

31. colon becomes covered witih adenomatous polyps after puberty - progresses to colon cancer unless resected
FAP
Citrate - acetyl coa from mito to cyto
Methionine encode by only 1 codon (AUG)
MRNA

32. Adenosine deaminase deficiency is an important cause of what immunodeficiency?
Dec DNA - dec lymphos leads to SCID
Marasmus - muscle wasting
Fed
Marfans

33. What does the TCA cycle produce per 1 acetyl CoA
Oxidizes substrate
African Americans and Asians
Males are infertile due to bilateral absence of vas deferens
3 NADH - 1 FADH2 - 2 CO2 - 1 GTP = 12 ATP (x2 per glucose)

34. What is the results of vit B1 def
FMR1 gene - methylation - associated with chromosomal breakage
Impaired glucose breakdown leading to ATP depletion; highly affected aerobic tissues like brain and heart affected first
Connective tissue
After day 1

35. What is mosaicism and give an example
PFK - rate limiting enzyme
UDP glucose pyrophosphorylase
Inhibits 50S peptidyltransferase
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

36. What causes patau's syndrome and What is it
Euchromatin
B6
Trisomy 13 - severe mental retardation - rocker bottom feet - micophthlamia - microcephaly - cleft lip/palate - holoprosencephaly - polydactyly - congenital heart disease - death usually within the first year
Dec methionine - inc cystiene - inc B12/folate

37. What causes Down syndrome
Meiotic nondisjunction of homologous chromosomes (associated with advanced maternal age) leading to trisomy 21
Result from phagocytic removal of heinz bodies my macs - G6PD def
Carnitine shuttle - acyl - coa from cyto to mito
Mucus secreting globlet cells and antibody secreting plasma cells

38. What is the structure of elastin
Riboflavin - cofactor in oxidation and reduction (FAD and FMN are derived from riboflavin)
Tropoelastin with fibrillin scafolding
Converted to THF - a coenzyme for one - carbon transfer/methylation reactions - important for synthesis of nitrogenous bases in DNA and RNA
HMG- CoA synthase

39. What is the RDE of glycogenolysis
Glycogen phosphorylase
Change resulting in early stop codon
Glycogen and FFA oxidation; glucose conserved for final sprinting
Glycolysis - fatty acid synthesis - HMP shunt - protein synthesis (RER) - steroid synthesis (SER)

40. What chromosome is the NF gene on...
Oligomycin
Oxalacetate
Mcardle's - skeletal muscle glycogen posphorylase
17 - 17 letters in von Recklinghausen

41. What is the fxn of vit D
Delayed wound healing - hypogonadism - dec in adult hair - dysguesia - anosmia - may predispose to EtOH cirrhosis
Inc intestinal absorption fo calcium and phosphate - inc bone resorption
II - VII - IX - X (1972) protein C and S
32 - malate aspartate shuttle

42. What are purines made from
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
IMP precursor
AMP - fructose 2 -6 BP
Adenylyl cycle - inc cAMP - inc PKA - glycogen phosphorylase kinase activated - glycogen phosphoylase active - glycolysis

43. What are the blood glucose levels maintained by for days 1-3
Inc intake of ketogenic nutrients - high in fact content or inc lysine or leucine
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)
Von hippel lindau - 3
Dec DNA - dec lymphos leads to SCID

44. What does vit B3 def result in
Inherited lysosomal storage disorder; failure of addition of mannose 6 phosphate to lysosomal proteins - enzymes secreted outside of cell instead of lysosomes
Diphyllobothrium latum
Glossitis - severe = pellagra - diarrhea - dermatitis - dementia
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

45. Eukaryotic and prokaryotic DNA synthesis is blank and involves both blank and blank strands
Semiconservative - continuous and discontinuous strands (okazaki fragments)
1 gene had >1 effect on an individuals phenotype - PKU causes many seemingly unrelated symptoms ranging from mental retardation to hair/skin changes
Pantothenate - essential component of CoA - a cofactor for acyl transfers and fatty acid synthase
Flank pain - hematuria - HTN - progressive renal failure

46. What is the hardy weinber heterozygote prevalence
Flagella - cilia - mitotic spindles
Same AA - often base change in 3rd position of codon (tRNA wobble)
Niacin - constituent of NAD and NADP - derived from tryptophan
2pq

47. What amino acid makes up most of the octamer
Lariat shape in order and remove intron precisely and join 2 exons
Lysine and arginine
Glycogen phosphorylase
Huntingtons

48. What enzyme catalyzes the rxn from pyrvuate to Acetyl - CoA and what inhibits it
Pyruvate dehydrogenase - ATP - NADH - acetyl - CoA
Glycolysis and the glycogen synthesis in the liver - hexokinase or glucokinase
Nonreciprocal chromosomal translocation that commonly involves chromosome pairs 13 - 14 - 15 - 21 - 22
Alcohol version of glucose - can trap glucose in cell - aldose reductase

49. What is sorbitol - how and why is it made
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Palate - facial and cardiac defects
Tryosine hydroxylase
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

50. What is the activated carrier for aldehyddes
LPL def - or altered apoCII - elevated TG and cholesterol - causes pancreatitis - hepatosplenomegaly and eruptive/pruritic xannthomas - no risk of atherosclerosis
TTP
Alcohol version of glucose - can trap glucose in cell - aldose reductase
Inhibits lipoic acid - vomiting - rice water stools - garlic breath