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Biochem Shelf Review
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357
Biochemistry
Graduate
11/15/2020

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Cards

Term
DNA is stored in what formed in the nucleus?
Definition
Condensed chromatin
Term
What forms nucleosome "beads" in chromatin?
Definition
DNA looped around postiviely charged histones
Term
What histone ties nucleosome beads together?
Definition
H1
Term
What is unique about the histone H1?
Definition
Only histone not in the nucleosome core
Term
What is the name for condensed, transcriptionally inactive, sterically inaccessible DNA?
Definition
Heterochromatin
Term
What is the name for less condensed, transcriptionally active, sterically accessible DNA?
Definition
Euchromatin
Term
How many histones make up a nucleosome?
Definition
8 histone octamer
Term
What histones make up the nucleosome core?
Definition
2 sets of H2A, H2B, H3, H4
Term
Which nucleotides are purines?
Definition
Adenine, Guanine (mnemonic: PURe As Gold)
Term
What nucleotides are pyrimidines?
Definition
Cytosine, Uracil, Thymine (mnemonic: CUT the PY)
Term
Deamination of cytosine makes what nucleotide?
Definition
Uracil
Term
What amino acids are necessary for purine synthesis?
Definition
Glycine, Aspartate, Glutamine
Term
What is the purine precursor in de novo synthesis?
Definition
IMP
Term
What is the pyrimidine precursor in de novo synthesis?
Definition
Orotate with PRPP added later
Term
What pathways involve carbamoyl phosphate?
Definition
De novo pyrimidine synthesis and the urea cycle
Term
Ornithine transcarbamoylase deficiency in the urea cycle leads to an accumulation of what?
Definition
Carbamoyl phosphate
Term
Excess carbamoyl phosphate is converted to what?
Definition
Orotic acid
Term
Methotrexate inhibits what?
Definition
Dihydrofolate reductase
Term
Orotic aciduria causes what conditions?
Definition
Megaloblastic anemia, increased orotic acid in urine
Term
Orotic aciduria results from a defect in what step of de novo pyrimidine synthesis? 
Definition
Conversion of orotic acid to UMP
Term
What enzymes are deficient in orotic aciduria?
Definition
orotic acid phosphoribosyltransferase or orotidine 5'-phosphate decarboxylase
Term
What is the mode of inheritence for orotic aciduria?
Definition
Autosomal recessive
Term
Adenosine deaminase deficiency causes what disease?
Definition
SCID = Severe Combined Immunodeficiency Disease
Term
Adenosine deaminase deficiency causes excess ATP  and dATP, preventing what?
Definition
DNA synthesis, results in decreased lymphocyte count
Term
Defective purine salvage due to the absence of HGPRT is characteristic of what disease?
Definition
Lesch-Nyhan Syndrome
Term
What is the mode of inheritence for Lesch-Nyhan syndrome?
Definition
X-linked recessive
Term
What is the function of HGPRT?
Definition
Converts hypoxanthine to IMP and guanine to GMP in the purine salvage pathway
Term
What are the "features" of the genetic code?
Definition
Unambiguous (1 codon = 1 amino acid), redundant (more than 1 codon may code for same amino acid), comaless (read from fixed starting point), universal (genetic code is conserved throughout evolution)
Term
What are exceptions to the universal feature of the genetic code?
Definition
mitochondria, archaebacteria, mycoplasma, some yeasts
Term
What kind of mutation does not result in the translation of a different amino acid?
Definition
Silent
Term
What kind of mutation leads to the translation of a different amino acid?
Definition
Missense
Term
What kind of mutation creates an early stop codon?
Definition
Nonsense
Term
What kind of mutation results in a misreading of all nucleotides downstream from the change?
Definition
Frame shift
Term
A particular sequence in the genome where DNA replication begins is known as what?
Definition
Origin of replication (single in prokaryotes, multiple in eukaryotes)
Term
Leading and lagging strands are synthesized at what location along the DNA template?
Definition
Replication Fork
Term
What unwinds DNA at the replication fork?
Definition
Helicase
Term
DNA supercoils are relieved by what?
Definition
DNA topoisomerases
Term
What enzyme creates a RNA primer on which DNA polymerase III can initiate replication?
Definition
Primase
Term
What DNA polymerase is found only in prokaryotes?
Definition
DNA polymerase I and III
Term
Which proofreads synthesized DNA in prokaryotes?
Definition
DNA polymerase III
Term
What degrades RNA primers and fills in gaps with DNA in prokaryotes?
Definition
DNA polymerase I
Term
What seals DNA fragments during DNA synthesis?
Definition
DNA ligase
Term
Okazaki fragments are found in what?
Definition
Lagging strand
Term
DNA is synthesized in what direction?
Definition
5' --> 3'
Term
A specific endonucleases being used to release damaged bases in order to allow DNA polymerase and ligase to fill and reseal the gap describes what kind of repair?
Definition
Nucleotide excision repair
Term
A specific glycosylase being used to recognize and remove a single damaged base to be replaced describes what kind of repair?
Definition
Base excision repair
Term
What is the most abundant type of RNA?
Definition
rRNA
Term
What is the mRNA start codon?
Definition
AUG, occasionally GUG
Term
The start codone AUG codes for what in eukaryotes?
Definition
Methionine
Term
What are the mRNA stop codons?
Definition
UGA, UAA, UAG (mnemonic: U Go Away, U Are Away, U Are Gone)
Term
The site where RNA polymerase and multiple other transcription factors bind to DNA upstream from the gene locus is called what?
Definition
Promoter
Term
What are the promoters found in eukaryotes?
Definition
TATA and CCAAT boxes
Term
The stretch of DNA that alters gene expression by binding transcription factors is known as what?
Definition
Enhancer
Term
Sites where negative regulators (repressors) bind on genes is know as what?
Definition
Silencer
Term
What is the function of RNA polymerase I?
Definition
rRNA synthesis in eukaryotes
Term
What is the function of RNA polymerase II?
Definition
mRNA synthesis in eukaryotes
Term
What is the function of RNA polymerase III?
Definition
tRNA synthesis in eukaryotes
Term
What other function does RNA polymerase have other than mRNA synthesis?
Definition
Opens DNA at promoter site
Term
What is the function of RNA polymerase in prokaryotes?
Definition
Only RNA polymerase complex in prokaryotes, produces all 3 kinds of RNA
Term
What is alpha-amanitin and its effects?
Definition
Found in death cap mushrooms, inhibits RNA polymerase II, lethal
Term
What are the steps of RNA processing in eukaryotes?
Definition
1. 5' cap
2. 3' Poly-A tail
3. Splicing out of introns 
Term
What must occur before RNA is transported out of nucleus?
Definition
Processing
Term
Antibodies to spliceosomal snRNPs are found in what disease?
Definition
Lupus
Term
The coding segments of DNA are known as what?
Definition
Exons
Term
The non-coding segments of DNA are known as what?
Definition
Introns
Term
What is tthe function of snRNPs?
Definition
Forms spliceosomes in order to join exons
Term
What is bound to the 3' end of tRNA?
Definition
The coded amino acid
Term
What enzyme is responsible for the accuracy of amino acid selection during protein synthesis?
Definition
Aminoacyl-tRNA synthetase
Term
Accuracy of base pairing is dependent on which nucleotides in an mRNA codon?
Definition
First 2
Term
GTP hydrolysis and initiation factors perform what function in protein synthesis?
Definition
Assembling of 40S ribosomal subunit with initiator tRNA
Term
tRNA binds to what site on ribosomes?
Definition
A site
Term
Translated codons are translocated to what part of the ribosome?
Definition
P site
Term
Translated codons are translocated to where on the ribosome?
Definition
P site
Term
What is the energy requirement for translation?
Definition
2ATP, 2GTP
Term
Inactive enzyme precursors are known as what?
Definition
Zymogens
Term
What is used to tag defective proteins for breakdown?
Definition
Ubiquitin
Term
Covalent alterations of proteins include what?
Definition
Phosphorylation, glycosylation, hydroxylation
Term
Cell cycles are regulated by what factors?
Definition
Cyclin-dependent kinases, cyclins, tumor suppressors
Term
Which cellular organelle is the site of steroid synthesis and detoxification of poisons and drugs?
Definition
Smooth ER
Term
The distribution center of proteins and lipids from the ER to the plasma membrane, lysosome, and secretory vesicles describes what organelle?
Definition
Golgi apparatus
Term
What other function does the golgi apparatus serve other than lipid and protein distribution?
Definition
Protein modification, proteoglycan assembly, protein insertion into membranes
Term
The failure of addition of mannose-6-phosphate to lysosome proteins resulting in lysosomal storage disorder and high plasma levels of lysosomal enzymes describes what disease?
Definition
I-cell disease
Term
What disease results in male and female infertility, recurrent sinusitis, and bronchiectasis due to dynein arm defect induced immotile cilia?
Definition
Kartagener's syndrome, associated with situs inversus
Term
High amounts cholesterol or long saturated fatty acid in plasma membranes has what effect?
Definition
Increases melting temp, decreases fluidity
Term
What is the most abundant protein in the human body?
Definition
Collagen
Term
Mnemonic for collagen types: Be So Totally Cool, Read Books
Definition
Type I = Bone, Skin, Tendon, Type II = Cartilage, Type III = Reticulum, Type IV = Basement membrane/basal lamina
Term
Type I collagen forms what structures?
Definition
Bone, skin, tendon
Term
Type II collagen forms what structures?
Definition
Cartilage
Term
Type III collagen forms what structures?
Definition
Reticulum
Term
Type IV collagen forms what structures?
Definition
Basement membrane or basal lamina
Term
What makes up collagen alpha chain sub-units?
Definition
Gly-X-Y polypeptide (X and Y are proline, hydroxyproline, or hydroxylysine)
Term
What cofactor is required for the hydroxylation of specific collagen proline and lysine residues?
Definition
Vit C
Term
Where does collagen hydroxylation and glycosylation occur?
Definition
ER
Term
Where are collagen alpha chains synthesized?
Definition
RER
Term
A triple helix of 3 collagen alpha-chains prior to modification is known as what?
Definition
Procollagen
Term
Cleavage of terminal regions of procollagen transforms it into what?
Definition
Tropocollagen
Term
What steps of collagen synthesis occur outside the cell?
Definition
Cleavage of terminal regions of procollagen into tropocollagen and cross linking into collagen fibrils
Term
How are collagen fibrils formed outside of the cell?
Definition
Staggered covalent lysine-hydroxylysine cross-linkage of tropocollagen
Term
Hyperexteinsible skin, easy brusing, and hypermobile joints caused by faulty collagen synthesis, usually type III, is characteristic of what disease?
Definition
Ehlers-Danlos syndrome
Term
Brittle bone disease most commonly associated with abnormal type I collagen leading to easily fractured bones, blue sclerae, and dental imperfections due to a lack of dentin characterizes what disease?
Definition
Osteogenesis imperfecta
Term
Osteogenesis imperfecta most commonly displays what pattern of inheritence?
Definition
Autosomal dominant
Term
Abnormal type IV collagen resulting in progressive hereditary nephritis and deafness is characteristic of what disease?
Definition
Alport's syndrome
Term
Alport's syndrome most commonly displays what pattern of inheritance?
Definition
X-linked recessive
Term
The stretchy protein within lungs, large arteries, elastic ligaments, vocal cords, that is rich in proline and glycine and uses fibrillin as scaffolding is known as what?
Definition
Elastin
Term
Elastin is broken down by elastase which is inhibited by what?
Definition
alpha-1-antitrypsin
Term
Marfan's syndrome is caused by a defect in what protein?
Definition
Fibrillin
Term
Alpha-1-antitrypsin deficiency can result in what?
Definition
Excess elastase activity causing emphysema
Term
The molecular biology laboratory procedure commonly used to amplify desired fragments of DNA is known as what?
Definition
Polymerase Chain Reaction (PCR)
Term
What are the 3 steps of PCR?
Definition
Denaturation, Annealing, Elongation
Term
What occurs during the denaturation step of PCR?
Definition
Heat denatures DNA to generate 2 separate strands
Term
What occurs during the annealing step of PCR?
Definition
During cooling, excess premade DNA primers anneal to specific sequences on strands to be amplified
Term
What occurs during the elongation step of PCR?
Definition
Heat stable DNA polmerase replicates the DNA sequence following each primer
Term
How are different sized DNA fragments separated for PCR amplification?
Definition
Agarose gel electrophoresis
Term
What blotting procedure is used to sequence DNA?
Definition
Southern Blot
Term
What blotting procedure is used to sequence RNA?
Definition
Northern Blot
Term
What blotting procedure is used to label and identify proteins?
Definition
Western Blot
Term
What technique is used to profile gene expression levels or to detect single nucleotide polymorphisms (SNPs)?
Definition
Microarrays
Term
What is used to rapidly test for antigen-antibody reactivity?
Definition
Enzyme-linked immunosorbent assay (ELISA)
Term
Using flourescent DNA or RNA probes to bind to specific genes of interest is called what?
Definition
Flourescence in situ hybridization (FISH)
Term
The process in which metaphase chromosomes are stained, ordered, and numbered according to morphology, size, arm-length ratio, and banding pattern is known as what?
Definition
Karotyping
Term
Imprinting is defined as what?
Definition
Differences in phenotype are dependant on maternal or paternal origin of mutation
Term
Prader-Willi and Angelman's syndrome are dependant on what type of heritability?
Definition
Imprinting
Term
If a patient inherits or develops a mutation in a tumor suppressor gene, what must occur before cancer can develop?
Definition
Complementary allele must be deleted/mutated (2 hit hypothesis)
Term
The phenomenon where cells in the body have differing genetic makeups is known as what?
Definition
Mosaicism
Term
Mosaicism in females often occurs as a result of what process?
Definition
X-linked inactivation
Term
An offspring receiving 2 copies of a chromosome from 1 parent and no copies from the other parent is known as what?
Definition
Uniparental disomy
Term
Prader-Willi syndrome is a result of what mutation?
Definition
Deletion of normally active paternal allele, an example of imprinting
Term
Angelman's syndrome is a result of what mutation?
Definition
Deletion of normally active maternal allele, an example of imprinting
Term
What mode of inheritence transmits diseases only through the mother?
Definition
Mitochondrial inheritance
Term
Which mode of inheritence has no male to male transmission?
Definition
X-linked recessive
Term
What autosomal dominant disease results in a cell signaling defect of fibroblast growth factor (FGF) receptor 3, resulting in dwarfism?
Definition
Achondroplasia
Term
What autosomal-dominant disease results in elevated LDL due to defective or absent LDL receptors with increased risk of myocardial infarction?
Definition
Familial hypercholesterolemia
Term
What autosomal dominant disorder is characterized by depression, dementia, and caudate atrophy due to low levels of GABA and ACh in the brain?
Definition
Huntington's disease
Term
Where is the mutation for Huntington's disease located?
Definition
Chromosome 4
Term
What kind of mutation results in Huntington's disease?
Definition
CAG repeats on chromosome 4
Term
Marfan's syndrome displays what mode of inheritence?
Definition
Autosomal dominant
Term
What autosomal dominant disease is characterized by cafe-au-lait spots, neural tumors, Lisch nodules, skeletal disorders, and increased tumor susceptibility?
Definition
Neurofibromatosis type 1 (aka von Recklinghausen's disease)
Term
Where is the mutation that causes Neurofibromatosis type 1 located?
Definition
Long arm of chromosome 17
Term
What autosomal dominant disease is characterized by bilateral acoustic neuroma and juvenile cataracts?
Definition
Neurofibromatosis type 2
Term
Where is the mutation that causes Neurofibromatosis type 2 located?
Definition
Chromosome 22
Term
What autosomal dominant disease is characterized by hemangioblastomas of the retina/crebellum/medulla, bilateral renal cell carcinomal, and other tumors?
Definition
von Hippel-Lindau disease
Term
What mutation causes Von Hippel-Lindau disease?
Definition
Deletion of VHL tumor suppressor gene on chromosome 3
Term
What autosomal recessive disease results in a defective CL- channel that causes secretion of abnormally thick mucus that plugs lungs, the pancreas, and the liver?
Definition
Cystic Fibrosis
Term
What mutation causes Cystic Fibrosis?
Definition
Defect in CFTR gene on chromosome 7, commonly a deletion of Phe 508. Causes abnormal protein folding and degradation of Cl- channel
Term
What can be used to treat Cystic Fibrosis?
Definition
N-acetylcysteine used to loosen mucous plugs
Term
G6PD deficiency follows what mode of inheritance?
Definition
X-linked recessive
Term
Hunter's syndrome follows what mode of inheritance? 
Definition
X-linked recessive
Term
Albinism, glycogen storage diseases, mucopolysaccharidoses, phenylketonuria, sickle cell anemias, and thalassemias all share what mode of inheritance?
Definition
Autosomal recessive
Term
What disease is characterized by accelerated muscle breakdown, weakness in pelvic girdle muscles, cardiac myopathy, and fibrofatty replacement of calf muscles?
Definition
Duchenne's muscular dystrophy
Term
What mutation causes Duchenne's muscular dystrophy?
Definition
X-linked frame shift mutation causing deletion of dystrophin gene
Term
What muscular dystrophy is similar to Duchenne's but less severe?
Definition
Becker's muscular dystrophy
Term
What X-linked disease affects the expression of the FMR1 gene and is associated with chromosomal breakage?
Definition
Fragile X Syndrome
Term
What trinucleotide repeats can be seen in Fragile X syndrome?
Definition
CGG
Term
Trisomy 21 results in mental retardation, flat faces, promient epicanthal folds, is associated with an increased risk in Alzheimer's disease, and is commonly known as what?
Definition
Down Syndrome
Term
The overwhelming majority (95%) of down syndrome cases are due to meiotic nondisjunction. What are the minor causes of down syndrome?
Definition
Robertsonian translocation (4%) and Down mosaicism (1%)
Term
Trisomy 18 resulting in severe mental retardation, rocker bottem feet, clenched hands, prominent occiput, congenital heart disease, and early infant death is known as what?
Definition
Edward's Syndrome
Term
Trisomy 13 resulting in severe mental retardation, rocker bottom feet, microcephaly, cleft lip/palate, holoprosencephaly, polydactyly, congenital heart disease, and early infant death is known as what?
Definition
Patau's Syndrome
Term
A genetic defect may arise when the long arm of 2 acrocentric chromosomes fuse at the centromere and the 2 short arms are lost. If the transolocation is unbalanced, developmental defects may occur. This phenomenon is known as what?
Definition
Robertsonian Translocation
Term
What disease exhibits symptoms such as microcephaly, moderate to severe mental retardation, high-pitched crying/mewing, epicanthal folds, and cardiac abnormalities?
Definition
Cri-du-chat syndrome
Term
What mutation causes Cri-du-chat syndrome
Definition
Congenital microdeletion of short arm of chromosome 5
Term
What disease is characterized by distinctive elfin facies, mental retardation, hypercaclemia, vit D sensitivity, well developed verbal skills, friendliness with strangers, and cardiovascular problems?
Definition
Williams Syndrome
Term
What causes Williams syndrome?
Definition
Congenital microdeletion of long arm of chromosome 7 (regions include elastin gene)
Term
What are the fat soluble vitamins?
Definition
Vit A, D, E K
Term
What are the water soluble vitamins?
Definition
Vit C, B 
Term
Another name for Vit B1 is what?
Definition
Thiamine
Term

Another name for Vit B2 is what?

Definition
Riboflavin
Term

 

Another name for Vit B3 is what?

 

Definition
Niacin
Term

Another name for Vit B5 is what?

Definition
Pantothenic acid
Term

Another name for Vit B6 is what?

Definition
Pyrodoxine
Term

Another name for Vit B12 is what?

Definition
Cobalmin
Term
Which B vitamins are stored in the liver?
Definition
Vit B12 and folate
Term
Which vitamin functions as an antioxidant, is a constituent of visual pigments, and is essential for normal differentiation of epithelial cells into specialized tissues?
Definition
Retinol (Vit A)
Term
Retinol (Vit A) deficiency may result in what?
Definition
Night blindness, dry skin
Term
Why must a pregnancy test be done before isotretinoin is prescribed for severe acne?
Definition
Excess Vit A may result in birth defects such as a cleft palate or cardiac abnormalities
Term
Thiamine (Vit B1) is a cofactor for what enzymes?
Definition
Pyruvate dehydrogenase, alpha-ketoglutarate dehydrogenase, transketolase, branched chain AA dehydrogenase
Term
What are the results of thiamine (Vit B1) deficiency?
Definition
Impaired glucose breakdown, ATP depletion, leads to Wernick-Korsakoff syndrome and beriberi
Term
Thiamine (Vit B1) deficiency may result from the excess consumption of what?
Definition
Alcohol
Term
Riboflavin (Vit B2) is a cofactor in what processes?
Definition
Oxidation and reduction such as in FADH2
Term
Cheilosis (inflammation of the lips) and corneal vascularization is seen in what deficiency?
Definition
Riboflavin (Vit B2) deficiency
Term
Niacin (Vit B3) is a constiuent in what reactions?
Definition
Redox reactions, NAD+ and NAD+
Term
What is required to synthesize Niacin (Vit B3)?
Definition
Tryptophan and B6
Term
Severe Niacin (Vit B3) deficiency leads to what symptoms?
Definition
Pellagra leading to diarrhea, dermatitis, and dementia
Term
Pantothenate (Vit B5) serves what function?
Definition
Essential component of CoA and fatty acid synthase
Term
Pantothenate (Vit B5) deficiency results in what symptoms?
Definition
Dermatitis, enteritis, alopecia, adrenal insufficiency
Term
What can induce a pyridoxine (Vit B6) deficiency?
Definition
Oral contraceptive
Term
What is the function of pyridoxine (Vit B6)?
Definition
Cofactor in transamination, decarboxylation, glycogen phosphorylase, cystathionine synthesis, and heme synthesis. Required for niacin synthesis from tryptophan
Term
What is the function of Cobalamin (Vit B12)?
Definition
Cofactor for homocysteine methyltransferase and methylmalonyl-CoA mutase
Term
What results from Cobalamin (Vit B12) deficiency?
Definition
Macrocytic, megaloblastic anemia, neurologic symptoms, abnormal myelin, may result in irreversible nervous system damage
Term
What test is used to detect for the origin of the Cobalamin (Vit B12) deficiency?
Definition
Schilling test
Term
What is the active form of Folic acid?
Definition
Tetrahydrofolate
Term
What is the function of folic acid?
Definition
Coenzyme for 1-carbon transfer/methylation reactions, important for synthesis of nitrogenous bases in DNA and RNA
Term
What drugs can cause a folic acid deficiency?
Definition
Phenytoin, Sulfonamides, MTX
Term
What is the most common vitamin deficiency in the US?
Definition
Folic acid deficiency
Term
What are the results of folic acid deficiency?
Definition
Macrocytic, megaloblastic anemia. No neurological symptoms are present. Can be caused by alcoholism and pregnancy.
Term
Intake of folic acid supplements in early pregnancy reduces the risk of what?
Definition
Neural tube defects
Term
What forms S-adenosyl-methionine (SAM)? 
Definition
ATP + methionine
Term
What is the function of S-adenosyl-methionine (SAM)?
Definition
Transfer of methyl units, required for conversion of norepinephrine to epinephrine
Term
Regeneration of methionine (and thus S-adenosyl-methionine) is dependant on what?
Definition
Vit B12 and folate
Term
Biotin acts as a cofactor for what enzymes?
Definition
Adds 1-carbon groups in carboxylation enzymes for pyruvate carboxylase, acetyl-CoA carboxylase, propionyl-CoA carboxylase
Term
What factors can induce biotin deficiency?
Definition
Excessive ingestion of raw eggs, AVID in egg whites bind biotin
Term
What is the function of Vitamin C?
Definition
Antioxidant, also facilitates iron absorption (keeps it in Fe2+ reduced state), hydroxylation of proline and lysine in collagen synthesis, conversion of dopamine to NE
Term
Vit C deficiency causes what condition?
Definition
Scurvy - swollen gums, bruising, anemia, poor wound healing
Term
What form of Vit D is consumed in milk and formed in sun-exposed skin?
Definition
D3
Term
What is the storage form of Vit D?
Definition
25-OH D3
Term
What is the active form of Vit D?
Definition
1,25-(OH)2 D3 (also known as calcitriol)
Term
What is the function of Vit D?
Definition
Increases intestinal absorption of calcium and phosphate, bone reabsorption
Term
Vit D deficiency causes what?
Definition
Rickets in children (bending bones), osteomalacia in adults (soft bones), hypocalcemic tetany
Term
Excess Vit D causes what?
Definition
Hypercalcemia, hypercalciuria, loss of appetite, stupor
Term
What is the function of Vit E?
Definition
Antioxidant, protects erythrocytes and membranes from free-radical damage (Vit E for Erythrocytes!)
Term
Vit E deficiency leads to what?
Definition
Erythrocyte fragility, hemolytic anemia, muscle weakness, neurodysfunction
Term
What is the function of Vit K?
Definition
Catalyzes gamma-carboxylation of glutamic acid residues on proteins associated with blood clotting, clotting factors II, VII, IX, X, and protein C and S
Term
How is Vit K synthesized?
Definition
By intestinal flora
Term
What is significant about warfarin?
Definition
Vit K antagonist
Term
What is the function of zinc?
Definition
Essential for a large number of enzymes, formation of zinc fingers (transcription factor motif)
Term
What occurs as a result of zinc deficiency?
Definition
Delayed wound healing, hypogonadism, hair loss, dysgeusia, anosmia, predisposition to alcoholic cirrhosis
Term
What is the limiting reagent in ethanol metabolism?
Definition
NAD+
Term
What are the actions of fomepizole?
Definition
Inhibits alcohol dehydrogenase
Term
What are the actions of disulfiram (antabuse)?
Definition
Inhibits acetaldehyde dehydrogenase, leads to acetaldehyde accumulation, attributes to hangover symptoms
Term
What are the two enzymes used in ethanol metabolism?
Definition
Alcohol dehydrogenase, acetaldehyde dehydrogenase
Term
What are the effects of ethanol metabolism on the NADH/NAD+ ratio?
Definition
Increases ratio
Term
What are the efffects of ethanol metabolism on reactions in gluconeogenesis? 
Definition
Diverts pyruvate to lactate and OAA to malate, inhibits gluconeogenesis, stimulates fatty acid synthesis
Term
Increased NADH/NAD+ ratio by action of ethanol metabolism has what effect on glucose level?
Definition
Inhibits gluconeogenesis, induces hypoglycemia
Term
What are the effects of ethanol metabolism on fatty acid synthesis? What are the consequences?
Definition
Increased FA synthesis, leads to hepatocellular steatosis (fatty liver)
Term
Protein malnutrition resulting in skin lesions, edema, liver malfunctions, decreased apolipoproteins due to liver malfunction, and common association with small children with swollen bellies describes what condition? 
Definition
Kwashiorkor
Term
Energy malnutrition resulting in tissue and muscle wasting, loss of subcutaneous fat, and variable edema describes what condition?
Definition
Marasmus
Term
Fatty acid oxidation, acetyl-CoA production, the TCA cycle,  and oxidative phosphorylation occurs where?
Definition
Mitochondria
Term
Glycolysis, FA synthesis, and the pentose phosphate pathway occurs where?
Definition
Cytoplasm
Term
Protein synthesis occurs where?
Definition
Rough ER
Term
Steroid synthesis occurs where?
Definition
Smooth ER
Term
Heme synthesis, Urea cycle, and Gluconeogenesis occurs in what part of the cell?
Definition
Both cytoplasm and mitochondria
Term
What enzymes utilizes ATP to add high-energy phosphate groups onto substrates?
Definition
Kinases
Term
What enzymes add inorganic phosphates onto substrates without using ATP?
Definition
Phosphorylases
Term
What enzymes remove phophate groups from substrates?
Definition
Phosphatases
Term
What enzymes oxidize substrates?
Definition
Dehydrogenases
Term
What enzymes add single carbons with the help of biotin?
Definition
Carboxylases
Term
What is the rate determining enzyme in glycolysis?
Definition
Phosphofructokinase-1 (PFK-1)
Term
What is the rate determining enzyme in gluconeogenesis?
Definition
Fructose-1, 6-biphosphatase
Term
What is the rate determining enzyme in the TCA cycle?
Definition
Isocitrate dehydrogenase
Term
What is the rate determining enzyme in glycogen synthesis?
Definition
Glycogen synthase
Term
What is the rate determining enzyme in glycogenolysis?
Definition
Glycogen phosphorylase
Term
What is the rate determining enzyme in the pentose phosphate pathway?
Definition
Glucose-6-phosphate dehydrogenase (G6PD)
Term
What is the rate determining enzyme in de novo pyrimidine synthesis?
Definition
Carbamoyl phosphate synthetase II
Term
What is the rate determining enzyme in de novo purine synthesis?
Definition
Glutamine-PRPP amidotransferase
Term
What is the rate determining enzyme in the urea cycle?
Definition
Carbamoyl phosphate synthetase I
Term
What is the rate determining enzyme in FA synthesis?
Definition
Acetyl-CoA Carboxylase (ACC)
Term
What is the rate determining enzyme in FA oxidation?
Definition
Carnitine acyltransferase I
Term
What is the rate determining enzyme in ketogenesis?
Definition
HMG-CoA synthase
Term
What is the rate determining enzyme in cholesterol synthesis?
Definition
HMG-CoA reductase
Term
How much net ATP is produced in anaerobic glycolisis per glucose?
Definition
2 ATP
Term
What are electron carriers?
Definition
NADH, NADPH, FADH2
Term
What are carriers of 1-carbon units?
Definition
Tetrahydrofolates
Term
What are carriers of CH3 (methyl) groups?
Definition
SAM
Term
What catalyzes the phosphorylation of glucose to yield glucose-6-phosphate in glycolysis?
Definition
Hexokinase or glucokinase
Term
What inhibits hexokinase?
Definition
G6P
Term
What inhibits glucokinase?
Definition
No direct feedback inhibition
Term
Between hexokinase and glucokinase, which is induced by insulin?
Definition
Glucokinase
Term
Which has a higher affinity (lower Km), hexokinase or glucokinase?
Definition
Hexokinase
Term
Where is hexokinase found?
Definition
Ubiquitous
Term
Where is glucokinase found?
Definition
Liver and beta-cells in pancreas
Term
Which enzymes in glycolysis require ATP?
Definition
Hexokinase/glucokinase, Phosphofructokinase-1
Term
What enzymes in glycolysis facilitate the production of ATP?
Definition
Phosphoglycerate kinase and pyruvate kinase
Term
RBCs are wholly dependant on what for energy? Why?
Definition
Glycolysis due to lacking mitochondria
Term
Excess pyruvate and alanine resulting in lactic acidosis implies what condition?
Definition
Pyruvate dehydrogenase deficiency, possibly due to alcoholism and B1 deficiency
Term
What process allows lactate generated during anaerobic metabolism to undergo hepatic gluconeogenesis to become a source of glucose for muscles and RBCs?
Definition
Cori cycle
Term
What are the non ATP products of the TCA cycle per acetyl-CoA
Definition
3NADH, 1FADH2, 2CO2, 1 GTP
Term
Rotenone, CN-, Antimycin A, and CO perform what actions?
Definition
ETC inhibition
Term
Oligomycin performs what actions?
Definition
Inhibits mitochondrial ATPase
Term
What are the irreversible enzymes in gluconeogenesis?
Definition
Pyruvate carboxylase, PEP carboxykinase, Fructose-1,6-bisphosphatase, Glucose-6-phosphatase
Term
What do odd-chain fatty acids yield that is not produced in even-chan FA metabolism?
Definition
Propionyl-CoA
Term
What is the primary source of NADPH?
Definition
Pentose phosphate pathway
Term
What are the key enzymes in the pentose phosphate pathway?
Definition
Glucose-6-P dehydrogenase and Transketolase
Term
Low levels of NADPH has what clinical effect?
Definition
Hemolytic anemia due to poor RBC defense against oxidizing agents
Term
How does NADPH help with the detoxification of free radicals and peroxides?
Definition
Keeps glutathione reduced
Term
What is the mode of inheritence for Glucose-6-phosphate dehydrogenase deficiency?
Definition
X-linked recessive
Term
What benefit is there to glucose-6-phosphate dehydrogenase deficiency?
Definition
Malarial resistance
Term
What creates heinz bodies?
Definition
Hemoglobin precipitation within RBCs
Term
Glucose-6-phosphate dehydrogenase deficiency results in low NADPH. What would indicate such a condition?
Definition
Heinz bodies
Term
What results from phagocytic removal of heinze bodies by macrophages?
Definition
Bite cells
Term
Hereditary deficiency of aldolase B results in what condition?
Definition
Fructose intolerance
Term
What is the mode of inheritance for aldolase B deficiency?
Definition
Autosomal recessive
Term
Fructose intolerance due to aldolase B deficiency has what effect on energy metabolism?
Definition
Frucotse-1-phosphate accumulates, causes a decrease in available phosphate, inhibits glycogenolysis and gluconeogenesis
Term
Essential fructosuria is caused by what?
Definition
Fructokinase defect
Term
What is the mode of inheritance for essential fructosuria?
Definition
Autosomal recessive
Term
What sign indicates essential fructosuria?
Definition
Fructose in blood and urine due to inability to absorb fructose
Term
What causes classic galactosemia?
Definition
Absence of galactose-1-phosphate uridyltransferase
Term
What accumulates in blood and urine in cases of galactokinase deficiency?
Definition
galactitol, galactose
Term
Failure to track objects or develop a social smile, infantile cataracts, and galactose in the blood and urine indicates what?
Definition
Galactokinase deficiency
Term
What is the alcohol form of stored glucose?
Definition
Sorbitol
Term
What enzyme is required for the conversion of glucose to sorbitol?
Definition
Aldose reductase
Term
What converts sorbitol to fructose?
Definition
Sorbitol dehydrogenase
Term
What causes lactase deficiency?
Definition
Loss of brush-border enzyme, can be hereditary or age-dependent
Term
What is the form of amino acids found in proteins?
Definition
L-form
Term
What amino acids are found in histones?
Definition
Arg, His
Term
What are the acidic amino acids in the body?
Definition
Asp, Glu
Term
What are the basic amino acids in the body?
Definition
Arg, Lys, His
Term
What transports ammonium?
Definition
Alanine and glutamine
Term
What might be given in order to decrease ammonia levels?
Definition
Benzoate or phenylbutyrate, limited protein in diet
Term
Whatt are the effects of excess ammonia?
Definition
Depletion of alpha-ketoglutarate leading to TCA cycle inhibition
Term
What is the most common urea cycle disorder?
Definition
Ornithine transcarbamoylase deficiency (X-linked recessive)
Term
Excess carbamoyl phosphate leading to high orotic acid and an inability to eliminate ammonia might be caused by what?
Definition
Ornithine transcarbamoylase deficiency
Term
What is the function of MAO and COMT?
Definition
Breakdown of catecholamines
Term
What amino acid is essential due to phenylketonuria?
Definition
Tyrosine
Term
What causes phenylketonuria?
Definition
Decreased phenylalanine hydroxylase or tetrahydrobiopterin cofactor
Term
What occurs as a result of maternal phenylketonuria?
Definition
Infant microcephaly, mental retardation, growth retardation, congenital heart defects
Term
Congenital deficiency of homogentisic acid oxidase causes what?
Definition
Alkaptonuria
Term
Homogentisic acid oxidase is involved in what pathway?
Definition
Tyrosine degradation
Term
Deficiency of tyrosinase or defective tyrosine transportors results in what?
Definition
Albinism
Term
What amino acid is essential for mealanin synthesis?
Definition
Tyrosine
Term
Cystathionine synthase deficiency, decreased affinity of cystathione synthase, or homocysteine methyltransferase deficiency can all cause what?
Definition
Homocystinuria
Term
Hereditary defects of renal tubular amino acid transporters for cysteine, ornithine, lysine, and arginine causes what?
Definition
Cystinuria
Term
What can cystinuria create in the kidneys?
Definition
Cystine kidney stones
Term
Blocked degradation of branched chane amino acids causes what disease?
Definition
Maple syrup urine disease
Term
What are the branched chain amino acids that cannot be degraded in maple syrup urine disease?
Definition
Ile, Leu, Val (I Love Vermont maple syrup)
Term
What blocks the degradation of branched chain amino acids in maple syrup urine disease?
Definition
Decreased alpha-ketoacid dehydrogenase
Term
What are the clinical effects of maple syrup urine disease?
Definition
CNS defects, death
Term
What autosomal-recessive disorder is characterized by defective neutral amino acid transporters on renal and intestinal epithelial cells?
Definition
Hartnup disease
Term
Hartnup disease can be indicated by what?
Definition
Tryptophan excretion in the urine, absorption from the gut, leads to pellagra
Term
Glucose-6-phosphatase deficiency is characteristic of what disease?
Definition
Von Gierke's Disease
Term
Lysosomal alpha-1,4-glucosidase (acid maltase) deficiency is characteristic of what disease?
Definition
Pompe's disease
Term
Deficiency in debranching enzyme used in glycogen synthesis is characteristic of what disease?
Definition
Cori's disease
Term
Skeletal muscle glycogen phosphorylase deficiency is characteristic of what disease?
Definition
McArdle's disease
Term
Von Gierke's disease displays what symptoms?
Definition
Glycogen storage disease, severe fasting hypoglycemia, high liver glycogen, high blood lactate, hepatomegaly
Term
Pompe's disease displays what symptoms?
Definition
Glycogen storage disease, cardiomegaly, can lead to early death
Term
Cori's disease displays what symptoms?
Definition
Glycogen storage disease, milder form of Von Gierke but with normal lactate levels, exhibits fasting hypoglycemia, liver glycogen, and hepatomegaly
Term
McArdle's disease displays what symptoms?
Definition
Glycogen storage disease, high muscle glycogen but inability to break it down, painful muscle cramps, myoglobinuria with strenuous exercise
Term
What is the most common lysosomal storage disease?
Definition
Gaucher's disease
Term
An inability to transport long chain fatty acids into the mitochondria resulting in toxic accumulation is characteristic of what?
Definition
Carnitine deficiency
Term
What are the products of FA and amino acid metabolism in the liver?
Definition
Acetoacetate and beta-hydroxybutyrate
Term
Fruity breath is a sign of what?
Definition
Ketoacidosis
Term
What is the source of energy within the first few seconds of strenuous exercise?
Definition
Stored ATP, creatine phosphate, anaerobic glycolysis
Term

 

What is the source of energy within the first few minutes of strenuous exercise?

 

Definition
Oxidative phosphorylation alongside stored ATP, creatine phosphate, anaerobic glycolysis
Term
What is the source of energy after a few hours of strenous exercise such as in a marathon run?
Definition
Glycogen and free FA oxidation, glucose is conserved for final sprinting
Term
What is the function of LCAT?
Definition
Esterification of cholesterol
Term
How long does it take for ketone bodies to become the main source of energy for the brain?
Definition
Weeks
Term
What are the essential fatty acids?
Definition
Linoleic and linolenic acid, arachidonic acid if linoleic acid is absent
Term
What degrades dietary triglycerides in the small intestine?
Definition
Pancreatic lipase
Term
What degrades triglycerides circulating in chylomicrons and VLDLs?
Definition
Lipoprotein lipase
Term
What degrades triglycerides in IDLs?
Definition
Hepatic TG lipase
Term
What degrades triglycerides in adipocytes?
Definition
Hormone sensitive lipase
Term
What mediates transfer of cholesterol esters to other lipoprotein particles?
Definition
Cholesterol ester transfer protein (CETP)
Term
What is the function of Apo A-I?
Definition
Activates LCAT
Term
What is the function of Apo B-100?
Definition
Binds LDL receptor, mediates VLDL secretion
Term
What is the function of Apo C-II?
Definition
Cofactor for lipoprotein lipase
Term
What is the function of Apo B-48?
Definition
Mediates chylomicron secretion
Term
What is the function of Apo E?
Definition
Mediates lipid remnant uptake by liver
Term
What transports cholesterol from liver to tissues?
Definition
LDLs
Term
What transports cholesterol from peripheral tissues to the liver?
Definition
HDLs
Term
What delivers dietary triglycerides to peripheral tissues?
Definition
Chylomicrons
Term
Which lipoprotein is secreted by the liver and delivers hepatic triglycerides to peripheral tissues?
Definition
VLDLs
Term
What is formed by degraded VLDLs and delivers triglycerides and cholesterol to the liver where they are degraded to LDLs?
Definition
IDLs
Term
What acts as a repository for apo C and apoE which are needed for chylomicron and VLDL metabolism?
Definition
HDLs
Term
Lipoprotein lipase deficiency or altered apolipoprotein C-II  characterizes what? 
Definition
I-hyperchylomicronemia
Term
I-hyperchylomicronemia causes plasma concentrations of what to rise?
Definition

Chylomicrons, triglycerides, and cholesterol 

Term
Absence of LDL receptors causing accelerated atherosclerosis, tendon xanthomas, and corneal arcus is characteristic of what?
Definition
IIa-familial hypercholesterolemia
Term

IIa-familial hypercholesterolemia causes an increase in plasma levels of what?

Definition
LDLs and cholesterol
Term
Hepatic overproduction of VLDLs causing pancreatis describes what disease?
Definition
IV-hypertriglyceridemia
Term
A hereditary inability to synthesize lipoproteins due to deficiencies in apoB-100 and apoB-48 describes what disease?
Definition
Abeta-lipoproteinemia
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