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182 Cards in this Set
- Front
- Back
Exceptions to universal genetic code
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Mitochondria, archaebacteria, Mycoplasma, and some yeast
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Type of DNA repair for T-T dimers?
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Nucleotide excision repair (mutated in xeroderma pigmentosum)
|
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Type of DNA repair for oxidized, alkylated, or deaminated bases?
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Base excision repair
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Condition due to defect in DNA mismatch repair
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Hereditary nonpolyposis colorectal cancer (HNPCC) (microsatellite instability)
|
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Which prokaryotic DNA polymerase has 5' --> 3' exonuclease activity?
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DNA Pol 1 (degrades RNA primers)
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What is alpha amanitin and what does it cause if ingested?
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It inhibits RNA polymerase II (normally makes mRNA) and causes liver failure if ingested.
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What is the initial eukaryotic RNA transcript called? (before processing)
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heterogeneous nuclear RNA (hnRNA)
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Who makes antibodies to spliceosomal snRNPs?
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Patients with lupus!
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Which enzyme is responsible for matching anticodons to the correct amino acids? Where does the energy come from?
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Aminoacyl-tRNA synthetase (uses ATP)
Binding of the charged tRNA to the codon uses GTP. |
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Which ribosomal subunit does the mRNA first bind to?
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The small one - 40S in eukaryotes, 30S in prokaryotes (with the help of eIFs)
|
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What are 4 examples of permanent cells (remain in G0)?
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Neurons, Cardiac cells, RBCs, Skeletal muscle cells
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What are two examples of stable/quiescent cells?
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Hepatocytes & Lymphocytes
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What are 4 examples of labile cells?
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Bone marrow, Gut epithelium, Skin, Hair Follicles
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List several cell types rich in RER
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Goblet cells (secrete mucus), plasma cells (secrete Abs), neurons (Nissl bodies, make enzymes/neurotransmitters)
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List several cell types rich in SER
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Liver hepatocytes, gonads, and adrenal cortex (SER = steroid hormone synthesis, drug/poison detox)
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Disease? Coarse facial features, clouded cornea, restricted joint movement, high plasma levels of lysosomal enzymes
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I-cell disease
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What does the Golgi apparatus do involving oligosaccharides?
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MODIFIES N-oligosacc on asn and ADDS O-oligosacc to ser and thr
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What are COP1 and COP2?
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Vesicular trafficking proteins: COP I (Golgi to ER), COP II (RER to cis Golgi)
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What happens between pro-collagen and tropocollagen?
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It is exocytosed from the cell & the terminals are cleaved.
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What happens between pre-pro-collagen and pro-collagen?
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It is hydroxylated (on proline and lysine) (with the help of Vit C) and glycosylated (on lysine) to become a triple helix
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Describe the cross-linking of collagen.
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It is covalently cross linked at lysine-hydroxylysine residues by lysyl oxidase (which uses Cu). Defect causes Ehlers-Danlos.
|
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What do desmin and vimentin stain for? What are they?
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Desmin = muscle
Vimentin = connective tissue They are both intermediate filaments. |
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Disease? Recurrent pyogenic infections, partial albinism, and peripheral neuropathy
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Chediak-Higashi syndrome (microtubule polymerization defect)
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Disease? Male & female infertility, bronchiectasis, recurrent sinusitis, situs invertus
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Kartagener's syndrome (immotile cilia - dynein arm defect)
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What are microtubules made of?
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Alpha and beta tubulin dimer helices (each dimer has 2 GTP bound)
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Disease? Multiple fractures, blue sclerae, hearing loss, dental imperfections, often confused with child abuse
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Osteogenesis imperfecta (brittle bone disease) (type I collagen)
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Disease? Hyperextensible joints, easy bleeding, hypermobile joints, berry aneurysms/organ rupture
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Ehler's Danlos (type III collagen)
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Disease? Hereditary nephritis and deafness, ocular disturbances
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Alport's syndrome (type IV collagen)
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Name 2 diseases of elastin & their pathophys
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Marfan's syndrome (fibrillin defect) and emphysema (alpha-1-antitrypsin deficiency)
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Disease? Mental retardation, seizures, ataxia, inappropriate laughter
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Angelman's syndrome
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Disease? Mental retardation, hyperphagia, obesity, hypogonadism, hypotonia
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Prader-Willi syndrome
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Definition of heteroplasmy
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Presence of both normal and mutated mtDNA --> results in variable expression of mitochondrial inherited disease
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What is X inactivation in females called? What can it cause if it's random?
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Lyonization. Can cause mosaicism if random.
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Dominant negative effect definition
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A heterozygote produces a nonfunctional altered protein that also prevents the normal gene product from functioning (ex: mutated tx factor that can still bind DNA)
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Marfanoid habitus can be caused by Marfan's syndrome, MEN 2B, and homocystinuria. What genetic term is this an example of?
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Locus heterogeneity (mutations at different loci can produce the same phenotype)
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Inheritance of hypophosphatemic rickets
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X-linked DOMINANT (phosphate wasting at proximal tubule)
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Pathophys of Leber's hereditary optic neuropathy
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degeneration of retinal ganglion cells and axons --> acute loss of central vision
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Disease/cause? Microcephaly, mental retardation, high pitched crying, epicanthal folds, cardiac abnormalities
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Cri-du-chat syndrome (microdeletion of short arm of chromosome 5)
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Symptoms of Williams syndrome (microdeletion of long arm of chromosome 7)
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"elfin" facies, mental retardation, hyper-Ca, well developed verbal skills, friendliness, CV problems
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Trinucleotide repeats: CAG, GAA, CTG, CGG. Diseases?
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Huntington's (CAG), Friedrich's ataxia (GAA), Myotonic dystrophy (CTG), Fragile X (CGG)
|
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Pregnancy quad screen results in Down syndrome
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Low AFP, low estriol, high beta-HCG, high inhibin A
|
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Shared symptoms between Edwards' and Patau's syndromes
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Severe mental retardation, rocker-bottom feet, congenital heart disease
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The "P"s of Patau's syndrome
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"Puberty" chromosome (13), cleft lip/Palate, holoProsencephaly, Polydactyly
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Disease? Micrognathia, low set ears, clenched hands, prominent occiput, death within 1 year
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Edwards' Syndrome (trisomy 18)
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Disease? Telangiectasia, recurrent epistaxis, skin discoloration, AVM
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Hereditary hemorrhagic telangiectasis (Osler-Weber-Rendu syndrome)
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Findings with NF1 (von Recklinghausen's disease)?
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cafe-au-lait spots, neural tumors, Lisch nodules (pigmented iris hamartomas), scoliosis, optic pathway glioma
|
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Pathophys of VHL?
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Deletion of VHL (tumor suppressor) gene (chromosome 3) --> constitutive expression of HIF (txn factor) --> activation of angiogenic growth factors
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Findings with Fragile X (FMR1 gene)
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eXtra-large testes, jaw, & ears, autism, mitral valve prolapse
|
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How are muscular dystrophies diagnosed?
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Muscle biopsy and increased CPK
|
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Several uses of N-acetylcysteine
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CF (loosen mucus plugs), prevent kidney disease due to dye, acetaminophen overdose
|
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2 enzymes that B12 is a cofactor for
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Homocysteine methyltransferase (Homocys --> met) and methylmanolyl-CoA mutase (methylmal-CoA --> succinyl CoA)
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Form of methionine that transfers methyl unit
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S-adenosyl-methione (SAM) (regeneration is dependent on B12 and folate)
|
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Dermatitis, enteritis, alopecia, adrenal insufficiency. Vitamin deficiency?
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Vitamin B5 (pantothenate). Could also be biotin.
|
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Causes of pellagra (B3 deficiency)?
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Hartnup disease, carcinoid syndrome, INH (dec B6)
|
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What types of tissue does B1 deficiency affect first?
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Highly aerobic tissues (brain and heart) affected first --> polyneuritis, high output heart failure, Wernicke-Korsakoff, etc
|
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Cheilosis, corneal vascularization. Vitamin deficiency?
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B2 (riboflavin)
|
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Convulsions, hyperirritability, peripheral neuropathy, sideroblastic anemia. Vitamin deficiency?
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B6 (pyridoxine)
|
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Weak immune response, swollen gums, bruising, hemarthrosis, anemia, poor wound healing. Vitamin deficiency?
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Vitamin C (scurvy)
|
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Increased fragility of erythrocytes, muscle weakness, posterior column/spinocerebellar tract demyelination. Vitamin deficiency?
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Vitamin E (antioxidant)
|
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Biotin is a cofactor for what type of reaction?
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Carboxylation!
Pyruvate carboxylase, Acetyl-CoA carboxylase, and Propionyl CoA carboxylase |
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How does ethanol cause hypoglycemia? What else is a consequence of this mechanism?
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Increases NADH/NAD+ ratio in liver --> diverts pyr to lactate and OAA to malate --> inhibits gluconeogenesis. ALSO causes fatty change in liver due to increased fatty acid synthesis.
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Decreased adult hair, delayed wound healing, hypogonadism, dysgeusia, anosmia. Deficiency?
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Zinc
|
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Inhibitor of alcohol dehydrogenase and use?
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Fomepizole. Used as antidote for methanol or ethylene glycol poisoning.
|
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4 uses of NADPH
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1. Anabolic reactions
2. Respiratory burst (NADPH oxidase) 3. P-450 reductase 4. Glutathione reductase (GSSG --> GSH) |
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Which 3 pathways take place in both the mitochondria and the cytosol?
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Heme synthesis, Urea cycle, Gluconeogenesis (HUGs take "two")
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TPP: Vitamin it comes from and enzymes it's a cofactor for?
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From Vitamin B1 (thiamine). Cofactor for PDH (glycolysis), alpha-KG Dhase (TCA), TK (HMP shunt), branched-chain aa Dhase
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4 things pyruvate can be converted to
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Alanine (via ALT), oxaloacetate (PC), acetyl CoA (PDH), lactate (LDH)
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Findings with arsenic intake
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Rice water stool, garlic breath, and vomiting
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Cofactors for PDH
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TPP (B1), FAD (B2), lipoic acid, NADH (B3), CoA (B5)
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Oligomycin inhibits what?
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ATPase --> proton gradient builds up
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What 2 types of oxidative phosphorylation poisons DECREASE the proton gradient?
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Electron transport inhibitors (rotenone, CN-, antimycin A, and CO) and uncoupling agents (2,4-DNP and aspirin)
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Do odd or even chain FAs produce products that can undergo gluconeogenesis?
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ODD chain FAs (propionyl CoA → methylmalonyl CoA → succinyl CoA → OAA → gluconeogenesis)
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Most common human enzyme deficiency & histo findings?
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G6PD. See Heinz bodies (oxidized Hgb) and Bite cells.
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Aldolase A vs B?
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Aldolase A: present in normal glycolysis (F-1,6-BP to DHAP and G3P).
Aldolase B: breaks down F-1-P to DHAP and glyceraldehyde. |
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What sugar can cause infantile cataracts?
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Galactose (via galactitol). Enzyme deficiencies include galactokinase or galactose-1-phosphate uridyltransferase.
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Why does sorbitol accumulate in the lens, retina, and kidney, and Schwann cells?
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They have aldose reductase (glucose → sorbitol) BUT lack sorbitol Dhase, which would otherwise convert sorbitol to fructose.
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Ketogenic only amino acids?
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Leu and Lys (used as treatment for PDH deficiency)
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Glucogenic only amino acids?
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Val, Arg, His, Met (“Valium Are His Methods”)
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Glucogenic AND ketogenic amino acids?
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Ile, Phe, Thr, Trp
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Which steps of the urea cycle occur in the mitochondria?
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Carbamoyl phosphate synthetase I (rate limiting step) and ornithine transcarbamoylase
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What are two hyperammonemia treatments that bind amino acids and lead to their excretion?
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Phenylbutyrate and benzoate
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What reaction is SAM used as a methyl donor for?
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NE to Epi and DNA methylation (imprinting)
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What 3 compounds arise from arginine?
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Creatine, Urea, NO
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What form does glucose need to be in to be utilized for glycogen?
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UDP-glucose (glucose-1-phosphate is immediate precursor)
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List 3 causes of albinism.
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1) Deficiency of tyrosinase (synthesis of melanin from tyrosine), 2) Defective tyrosine transporters, 3) Lack of migration of NCCs
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3 causes of homocystinuria.
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1) Cystathionine synthase deficiency, 2) Decreased affinity of cystathionine synthetase for PLP (B6), 3) Homocysteine methyltransferase deficiency
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Disease? FTT, steatorrhea, acanthocytosis, ataxia, night blindness.
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Abetalipoproteinemia (deficient apoB-100 and apoB-48)
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How much energy do you get from 1g of protein or carb compared to 1g of fat?
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1 g protein/carb = 4kcal, 1 g fat = 9kcal
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Which has greater muscle wasting: kwashiorkor or marasmus?
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Marasmus. "M" for "muscle" wasting.
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Top 2 causes of mental retardation as a result of chromosomal abnormality?
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1. Down syndrome
2. Fragile X syndrome Fragile X is top cause of INHERITED mental retardation. |
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Amino acids necessary for purine synthesis?
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Glutamine
Aspartate Glycine |
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Compounds that comprise purine ring?
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Glutamine
N10-Formyl-THF Glycine Aspartate CO2 |
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Components of pyrimidine ring?
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Cabamoyl phosphate and Aspartate
|
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Pathway from UMP to dTMP?
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UMP --> UDP --> dUDP --> dUMP --> dTMP
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What inhibits ribonucleotide reductase?
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Hydroxyurea
|
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What does 5-FU inhibit?
|
Thymidylate synthase
(dUMP --> dTMP) |
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Effect of 6-mercaptopurine (6-MP)?
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Blocks de novo purine synthesis (at several steps)
|
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CPS II catalyzes what reaction?
|
ATP + CO2 + gln --> carbamoyl phosphate
- 1st step of de novo pyrimidine synthesis |
|
GMP, IMP, and AMP breakdown?
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GMP --> guanosine --> guanine
IMP --> inosine --> hypoxanthine AMP --> adenosine --> inosine --> hypoxanthine --> xanthine --> uric acid |
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What kind of DNA repair is used for dsDNA breaks (as a result of ionizing radiation)?
|
Nonhomologous end joining
- brings together 2 ends of DNA fragments |
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First step of nucleotide vs base excision repair?
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Nucleotide excision: **endonuclease** releases oligonucleotide with damaged bases
Base excision: specific **glycosylases** recognize and remove damaged DNA bases |
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Key intron nucleotides?
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Exon 1 -- GU ------ A ------ AG -- Exon 2
|
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What happens to introns after splicing?
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They stay in the nucleus
|
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Eukaryotic vs prokaryotic RNA polymerase?
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Prokaryotes: 1 RNA polymerase makes all 3 kinds of RNA
Eukaryotes: RNA Pol I (rRNA), RNA Pol II (mRNA), RNA Pol III (tRNA) |
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Polyadenylation signal? Corresponding sequence at 3' end of DNA strand?
|
AAUAAA
On DNA: AATAAA |
|
AUG significance in eukaryotes vs prokaryotes?
|
Eukaryotes: codes for methionine
Prokaryotes: codes for formyl-methionine (f-Met) |
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How much energy does the aa-tRNA bond contain?
|
Enough for the formation of the peptide bone.
- Aminoacyl tRNA synthetase uses ATP to form the bond |
|
Different aspects of tRNA structure?
|
Acceptor stem (covalently binds aa)
T loop (binds ribosomes) Variable loop Anticodon loop D loop (has dihydrouracil) |
|
What do aminoglycosides inhibit?
|
Formation of the initiation complex --> cause misreading of mRNA
|
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What is needed for translation initiation?
|
GTP for translocation, initiation factors (eIFs), and 40S ribosomal subunit with initiator tRNA
|
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Site of addition of N-linked vs O-linked oligosaccharides?
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N-linked oligosacchs: added in RER --> modified in Golgi
O-linked oligosacch: added to serine and threonine residues in Golgi |
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Cyclins and CDKs: which are constitutively active?
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CDKs: constitutive and inactive
Cyclins: phase specific, activate CDKs |
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Location of Type I collagen?
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Bone, Skin, Tendon, Dentin, Fascia, Cornea, Late wound repair
|
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Location of Type II collagen?
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Cartilage (including hyaline), Vitreous body, Nucleus pulposus
|
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Location of Type III collagen (reticulin)?
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Skin, Blood vessels, Uterus, Fetal tissue, Granulation tissue
|
|
Location of Type IV collagen?
|
Basement membrane or Basal lamina
|
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What form of collagen is exocytosed from the fibroblast?
|
Pro-collagen
- terminal regions are cleaved outside the fibroblast, converting it to tropocollagen |
|
Cytoskeletal elements made from actin and myosin?
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Microvilli
Muscle contraction Cytokinesis Adherens junction |
|
Cytoskeletal elements made from microtubules?
|
Cilia
Flagella Mitotic spindle Neurons Centrioles |
|
Cytoskeletal elements made from intermediate filaments?
|
Vimentin
Desmin Cytokeratin Glial fibrillary acid protein (GFAP) Neurofilaments |
|
Drugs that act on microtubules?
|
1. Mebendazole/thiabendazole
2. Griseofulvin 3. Vincristine/vinblastine 4. Paclitaxel 5. Colchicine |
|
What does a southwestern blot identify?
|
DNA binding proteins by their binding to oligonucleotides
|
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Elastin composition and locations where it's found?
|
Lungs, large arteries, elastic ligaments, vocal cords, ligamenta flava
Rich in non-glycosylated glycine and proline. |
|
What types of diseases have variable expression in the population due to heteroplasmy?
|
Diseases w/ mitochondrial inheritance
Ex: mito myopathies, Leber's hereditary optic neuropathy |
|
X-linked mucopolysaccharidosis and sphingolipidosis?
|
Mucopolysaccharidosis: Hunter's
Sphingolipidosis: Fabry's (All of the rest of each are autosomal recessive) |
|
In what muscles does weakness begin in Duchenne's muscular dystrophy?
|
Begins in pelvic girdle muscles and progresses superiorly
|
|
Gene defect in Fragile X?
|
FMR1 gene
- methylation and expression are affected |
|
Microdeletions: Short arm of chromosome 5? Long arm of chromosome 7?
|
Cri-du-chat: short arm of 5
Williams: long arm of 7 - deleted region includes elastin gene |
|
What does ultrasound show in Down syndrome?
|
Nuchal translucency
|
|
Genetic causes of Down syndrome?
|
95% meiotic non-disjunction (associated w/ AMA)
4% robertsonian translocation 1% Down mosaicism (no maternal assoc) |
|
Telangiectasia, recurrent epistaxis, skin discolorations, AVMs. Disease?
|
Osler-Weber-Rendu syndrome
(hereditary hemorrhagic telangiectasia) |
|
Juvenile cataracts and bilateral acoustic schwannomas. Disease?
|
Neurofibromatosis type 2
- NF2 gene on chromosome 22 |
|
What can worsen thiamine (B1) deficiency?
|
Glucose infusion
- impaired glucose breakdown/ATP depletion |
|
Function of vitamin B5 (pantothenate)?
|
Essential component of CoA (cofactor for acyl transfers) and fatty acid synthase
|
|
Functions of vitamin B6 (pyridoxine)?
|
Converted to PLP which is used in:
Transamination (ALT/AST) Decarboxylation reactions Glycogen phosphorylase Cystathionine synthesis Heme synthesis |
|
Who is folic acid deficiency commonly seen in?
|
Alcoholics and pregnancy/OCP use.
Also elderly, goat's milk, and malabsorption. |
|
Location of alcohol vs aldehyde dehydrogenase?
|
Alcohol dhase: in cytosol
Aldehyde dhase: in mitochondria |
|
Rate limiting step of gluconeogenesis?
|
Fructose-1,6-bisphosphatase
|
|
Rate limiting step of TCA cycle?
|
Isocitrate dehydrogenase
|
|
Rate limiting step of glycogen synthesis and glycogenolysis?
|
Glycogen synthesis: glycogen synthase
Glycogenolysis: glycogen phosphorylase |
|
Rate limiting step of fatty acid synthesis and oxidation?
|
FA synthesis: Acetyl-CoA carboxylase (ACC)
FA oxidation: Carnitine acyltransferase I |
|
3 factors that are increased in exercise and activate PDH?
|
Increased NAD+/NADH ratio
Increased ADP Increased Ca |
|
Where is anaerobic glycolysis the major form of glycolysis?
|
RBCs
Leukocytes Kidney medulla Lens Testes Cornea |
|
Names and locations of irreversible enzymes in gluconeogenesis?
|
Glucose-6-phosphatase: ER
Fructose-1,6-bisphosphatase: cytosol PEP carboxykinase: cytosol Pyruvate carboxylase: mitochondria |
|
Energy source of pyruvate carboxylase and PEP carboxykinase?
|
Pyruvate carboxylase: uses ATP
(also uses biotin as a cofactor) - activated by acetyl CoA PEP carboxykinase: uses GTP |
|
Transketolases participate in which part of the HMP shunt?
|
Nonoxidative (reversible)
Ribulose-5-P --> TK --> Ribose-5-P, G3P, F6P |
|
Products of the oxidative (irreversible) part of the HMP shunt?
|
CO2, 2 NADPH, and Ribulose-5-P
Catalyzed by Glucose-6-P-Dhase |
|
Sites in body where HMP shunt takes place?
|
Lactating mammary glands, liver, adrenal cortex, RBCs
|
|
Two ways that NADH can enter the mitochondria?
|
Malate-aspartate shuttle
Glycerol-3-phosphate shuttle |
|
Effects of aldolase B deficiency?
|
Fructose intolerance
- Fructose-1-phosphate accumulates --> decreases available phosphate --> inhibits glycogenolysis and gluconeogenesis - Hypoglycemia, jaundice, cirrhosis, vomiting |
|
How might galactokinase deficiency present?
|
May initially present as failure to track objects or to develop a social smile.
|
|
Pathway of reduction starting with G6P?
|
G6P reduces NADP+ --> NADPH reduces GS-SG --> GSH reduces H2O2 --> 2H2O
H2O2 comes from respiratory burst or from invading organisms |
|
What does catalase do?
|
Catalase uses GSH to reduce H2O2 to H2O (and GSSG)
Catalase positive organisms neutralize their own H2O2 (bad for patients with CGD) |
|
Signs of ammonia intoxication?
|
Tremor, Slurring of speech, Somnolence, Vomiting, Cerebral Edema, Blurred Vision
|
|
Which amino acids are required during periods of growth?
|
His, Arg
|
|
PNMT catalyzes what reaction?
|
NE --> Epi
Stimulated by cortisol from venous drainage from adrenal cortex through medulla. |
|
B6 is required for amino acid conversions into what?
|
Tryptophan --> Niacin
Histidine --> Histamine Glycine --> porphyrin Glutamate --> GABA |
|
Pathway from glucose to glycogen?
|
Glucose-6-phosphate --> glucose-1-phosphate --> UDP-glucose --> glycogen
|
|
Glycogen phosphorylase: active in phosphorylated or dephosphorylated state?
|
Active when phosphorylated --> glycogenolysis
Intracellular Ca/calmodulin phosphorylates glycogen phosphorylase kinase which phosphorylates glycogen phosphorylase |
|
What 2 factors increase cAMP to stimulate glycogenolysis?
|
Glucagon (liver) and Epinephrine (liver and muscle)
--> Effect is to activate PKA which phosphorylates glycogen phosphorylase kinase Insulin leads to activation of protein phosphatase. |
|
Cause of cystinuria?
|
Hereditary defect of renal tubular amino acid transporter for cysteine, ornithine, lysine, and arginine in the PCT of the kidneys.
|
|
Cystine kidney stones and treatment?
|
Cystine staghorn calculi. Hexagonal in shape.
Treat with acetazolamine to alkalinize the urine. |
|
Findings in alkaptonuria (ochronosis)?
|
Dark connective tissue, brown pigmented sclera, urine that turns black on standing, debilitating arthralgias.
Caused by homogentisic acid oxidase deficiency --> buildup of homogentisate |
|
Von Gierke's vs Cori's disease?
|
Cori's: milder form of Von Gierke's
- gluconeogenesis is still intact because glucose-6-phosphatase is intact - defect is debranching enzyme (alpha-1,6-glucosidase) |
|
Muscle cramps but no lactic acid with exercise. Disease?
|
McArdle's disease (type V glycogen storage disease)
- deficient skeletal muscle glycogen phosphorylase (myophosphorylase) |
|
At what point do ketone bodies become the main source of energy for the brain and heart?
|
After 3rd day of starvation
- amount of adipose store determines survival time |
|
HMG CoA reductase reaction?
|
HMG CoA to mevalonate
2/3 of plasma cholesterol ends up being esterified by lecithin-cholesterol acyltransferase (LCAT) |
|
What are ketone bodies made from and metabolized to?
|
Made from HMG CoA
Metabolized by brain to 2 molecules of acetyl CoA |
|
Deficiency of carnitine results in what?
|
Inability to transport LCFAs into mitochondria --> results in toxic accumulation.
Causes weakness, hypotonia, and hypoketotic hypoglycemia. |
|
Changes in acyl-CoA dehydrogenase deficiency?
|
Increased dicarboxylic acids
Decreased glucose and ketones |
|
What does A-I apolipoprotein do?
|
Activates LCAT
|
|
What do apolipoproteins E3 and E4 do?
|
VLDL and chylomicron remnant uptake
|
|
What does HDL act as a repository for?
|
ApoC and ApoE (needed for chylomicron and VLDL metabolism)
|
|
Hepatic overproduction of VLDL causes what type of familial dyslipidemia?
|
Type IV - hypertriglyceridemia
|
|
LPL or altered apolipoprotein C-II cause what type of familial dyslipidemia?
|
Type I - hyperchylomicronemia
- elevated chylomicrons - causes pancreatitis, hepatosplenomegaly, eruptive/pruritic xanthomas |
|
Absent or decreased LDL receptors cause what type of familial dyslipidemia?
|
Type IIa - familial hypercholesterolemia
- increased LDL/cholesterol - causes atherosclerosis, tendon (Achilles) xanthomas, corneal arcus |
|
Beta-glucocerebrosidase deficiency causes buildup of what and what disease?
|
Buildup of Glucocerebrosides
Gaucher's disease (most common sphingolipidosis) |
|
Alpha-galactosidase deficiency causes buildup of what and what disease?
|
Ceramide trihexoside buildup
Fabry's disease (angiokeratoma corporis diffusum) |
|
Finding in Krabbe's disease and defect?
|
Peripheral neuropathy, developmental delay, optic atrophy, globoid cells.
Deficient galactocerebrosidase --> buildup of galactocerebroside |
|
Findings in Hurler's syndrome?
|
Developmental delay, gargoylism, airway obstruction, corneal clouding, short neck, CAD, hepatosplenomegaly
|
|
Enzyme deficiency in Hurler vs Hunter's syndrome?
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Hurler's: alpha-L-iduronidase
Hunter's: iduronate sulfatase |
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Metachromatic leukodystrophy?
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Central and peripheral demyelination with ataxia & dementia.
Deficient arylsulfatase A leads to buildup of cerebroside sulfate (sulfatides) |