Dideoxycytidine tri-phosphate cannot be incorporated into growing DNA chains.
Dideoxycytidine is an analog of the nucleoside deoxycytidine.
Dideoxycytidine tri-phosphate is used to terminate DNA chain elongation during DNA sequencing.
Dideoxycytidine has hydrogen groups on the 2’- and 3’-carbons of deoxyribose.
Dideoxycytidine is converted to a nucleoside tri-phosphate by cellular kinases.
Alters the specificity of the sigma factor of RNA polymerase.
Prevents the binding of RNA polymerase to promoters.
Increases the affinity of CAP for cAMP.
Decreases the affinity of CAP for cAMP.
Causes CAP to bind constitutively to CAP-binding sites.
Peroxisomes, Rough Endoplasmic Reticulum
Lipid Droplets, Smooth Endoplasmic Reticulum
Mitochondrion, Smooth Endoplasmic Reticulum
Lysosomes, Golgi Apparatus
Phosphorylation of amino acid side chains
Proteolytic cleavage of peptide bonds within the zymogen
Degradation of the enzyme
Converting activated enzymes to zymogens
This amino acid residue can form disulfide bonds under oxidizing conditions.
This residue can adopt a cis conformation of the peptide bond within a protein.
The side chain of this amino acid has multiple atoms that can participate in hydrogen bonds.
The side chain of this amino acid is positively charged at physiologic pH.
This amino acid can serve as an attachment site for O-linked polysaccharides (sugars) in glycoproteins.
Failure to inhibit gastric lipase
Excess undigested fats
Accumulation of Orlistat in the intestinal tract
Non-specific inhibition of many enzymes
His blood pressure of 135/82 identifies him as risk for hypertension
His BMI places him in the “normal” range
We should repeat the a1C and order a fasting plasma glucose (FPG) test on a non-urgent basis
His blood pressure is within the “normal” range
His hemoglobin a1C level of 6.2% identifies him as at increased risk of diabetes
Nitric oxide (NO) is released from Hb preferentially at sites of active metabolism, because a cysteine has a much higher affinity for NO in oxyhemoglobin than in deoxyHb.
Hemoglobin and myoglobin molecules can bind 2,3-bisphosphoglycerate, which decreases their affinity for oxygen.
Carbon dioxide increases the affinity of hemoglobin for oxygen both by binding to the N-terminus and through the Bohr effect.
The Hill Coefficient of hemoglobin indicates that hemoglobin tetramers have no more than three oxygen molecules bound.
Sites of active metabolism have higher concentration of carbonic acid, which shifts the hemoglobin oxygen dissociation curve to the left.
Gave them hydroxyurea to increase the synthesis of HbF.
Had them ingest a reducing agent to regenerate the oxygen binding form of Hb.
Gave them hydroxyurea to increase the synthesis of HbF.
Administered air with a higher percent of carbon dioxide than is normal, to compete with the carbon monoxide.
Administered 100% oxygen to displace the competitive inhibitor.
In going from a pO2 of 20mmHg to a pO2 of 100mmHg, stripped Hb takes up about three times as much oxygen as does Hb from whole blood, per mole of tetramer.
In going from a pO2 of 100mmHg to a pO2 of 20mmHg, Hb from whole blood releases about three times as much oxygen as does stripped Hb, per mole of tetramer.
The P50 value for stripped Hb is ~ 40mmHg lower than that for whole blood.
The P50 value for stripped Hb is ~ 15mmHg higher than that for whole blood.
Changing the pH would not affect the oxygen saturation curve of the stripped Hb.
Depends on the differing reactivity of the R and T forms of Hb
Leads to decreased blood flow at tissue sites with low oxygen pressure.
Can competitively inhibit cyanide poisoning.
Competes with carbon dioxide binding.
Is mediated by formation of C?-CH2-S-NO bond with Met.
Glucose 6-phosphate and enzyme E
Creatine phosphate and enzyme A
A vast excess of ATP
Pyrophosphate and enzyme D
Coupling of the synthesis of ATP to the reaction.
Enzyme catalysis of the reaction.
Generation of a higher temperature by the cell.
Coupling of ATP hydrolysis to the reaction.
Transfer of a phosphate group from the substrate to ADP.
Base + sugar + phosphate --> nucleotide
N2 + H2 --> ammonia
Sucrose --> CO2 + H2O
CO2 + H2O --> sugar
Amino acid + amino acid --> peptide
Disruption of the inner mitochondrial membrane stops ATP formation.
Complex I can only react with NADH from the matrix side while complex III can only reduce cytochrome c from the intermembrane space.
A pH gradient is set up across the inner mitochondrial membrane, with the pH higher in the matrix.
At least one component of each major electron transport complex is coded for by mt DNA.
Oxidation-reduction reactions of the electron transport chain generate a gradient of protons across the inner mitochondrial membrane.
A decrease in the cytosolic concentration of ADP.
A decrease in the activity of mitochondrial outer membrane transport proteins.
An increase in mitochondrial AMP.
An increase in mitochondrial ATP production.
A decrease in the cytosolic concentration of ATP.
The reduction of one NAD+.
The net consumption of one oxaloacetate.
The net synthesis of one citrate.
The production of six ATPs.
The release of two CO2.
CoA, lipoic acid, biotin and ATP
CoA, ATP, NAD+ and riboflavin
CoA, thiamine pyrophosphate and folic acid
CoA, lipoic acid, thiamine pyrophosphate and FAD
An event or exposure that occurs more often in people with a disease than without
An event, condition, or characteristic that plays an important role in disease occurrence..
An event that precedes the onset of a disease
A hazard or exposure that occurs in workplaces where people get sick.
All of the above
The bacterial genome shows a defect in lagging strand DNA chain elongation.
The bacterial genome shows a defect in mismatch repair.
The bacterial genome shows accumulation of telomeric repeats.
The bacterial genome shows a defect in the removal of RNA primers.
The bacterial genome shows an increased number of replication errors.
Transposons may either activate or inactivate a gene.
In transposition, both the donor and target sites must be homologous.
Integration of human immunodeficiency virus (HIV) in the human genome occurs via a “transposition-like” mechanism.
Transposons have “insertion sequences” that are recognized by transposase.
Transposons can move from one location to a different one within a chromosome.
Kinesins and dynein can move on the same structure.
The “power stroke” occurs when the products of hydrolysis are released.
All three classes of motors are ATPases.
Dynein moves on microtubules towards the centrosome.
When the subunit at the + end of the polymer is NTP, the end is more stable than if the nucleotide is NDP.
The energy of NTP hydrolysis is required for polymerization.
The nucleotide in the subunit at the end of the polymer affects the equilibrium constant of subunit addition at the end.
NTP hydrolysis occurs after polymerization.
Poly(A) binding protein
RNA polymerase inhibitors
Unlike bacterial genes, does not require specific DNA sequences.
Requires canonical -10 and -35 sequences.
Requires sequence specific binding by RNA polymerase II.
Is not a regulated step for determining the level of gene expression.
Requires general transcription factors that position RNA polymerase at the transcriptional start site.
Transcription factors promote disassembly of RNA Pol II to terminate transcription.
Several transcription factors may be involved in regulating the expression of a single gene.
General transcription factors are required for transcription of most, and probably all, genes.
Transcription factors often bind to specific DNA sequences.
Transcription factors can bind close to or even thousands of base pairs away from the promoter of genes they regulate.
Ligand (hormone) binding
Targeting of the receptor protein to the plasma membrane
Knowledge of drug atoms that do not interact with the protein is as useful in drug design as knowledge of drug atoms that contact the protein.
Because proteins interact with drugs like "locks and keys" knowledge of a protein's structure allows direct design of high-affinity drugs.
Most drug leads in structure assisted drug development projects are initially identified by screens of large libraries of synthetic or natural compounds in biochemical or cell-based assays.
Computational modeling, chemical synthesis, activity assays, and structure determination are steps that are all repeated multiple times during structure assisted drug development.
X-ray crystallography is the most commonly used method for determining atomic-resolution structures of protein-drug complexes.
Proteolysis followed by paper electrophoresis
Acid hydrolysis followed by amino acid analysis
Immunoblot (Western) analysis
Nuclear magnetic resonance (NMR) analysis
N-terminal amino acid sequence (Edman) analysis
The isoelectric point is 6.5
A region of maximum buffering occurs at "B".
The isoelectric form occurs at "C".
The pKa of the hydroxyl group substituent of the aromatic ring is 6.5.
At pH 10.0, the most abundant species has a net charge of –1.
In the small intestine, the concentration of neutral cimetidine is greater than the concentration of protonated cimetidine.
The concentration of protonated cimetidine is approximately the same in both fed and fasted stomachs.
The concentration of neutral cimetidine is approximately 100 times greater in the small intestine than in the duodenum.
In the duodenum, the concentration of neutral cimetidine is 10 times less than the concentration of protonated cimetidine.
In the fasted stomach, the concentration of neutral cimetidine is approximately 0.1 ng/ml.
Asp, Leu, Lys, Thr
Ala, Leu, Lys, Thr
Ala, Cys, Leu, Lys, Thr
Ala, Arg, Leu, Lys, Thr
Ala, Asp, Arg, Cys, Glu, Gly, Leu, Lys, Thr
The enzyme catalyzing reaction (4) is a isomerase
The enzyme catalyzing reaction (2) is a hydrolase
The enzyme catalyzing reaction (1) is an oxido-reductase
The enzyme catalyzing reaction (5) is a synthetase
The enzyme catalyzing reaction (3) is a lyase
Equilibrium constant for the reaction
Kinetics of heat inactivation
Its electrophoretic pattern is consistent with Sickle Cell Anemia.
It has a higher isoelectric point than HbA.
Its electrophoretic pattern is consistent with an Arg to Leu change in one beta-allele.
It has a higher oxygen affinity than HbA.
Its electrophoretic pattern is consistent with the compound heterozygote HbSC.
Increase intake of fluids.
Take medication to increase BPG levels in RBCs.
Take treatments to increase HbF levels
Avoid foods or situations that would lower body pH values.
Avoid high altitudes.
The beta-chain with the sickle cell mutation would not be expressed in the fetus.
HbA2 interferes with sickling.
There is not sufficient BPG in fetal red blood cells to cause sickling.
Fetal red blood cells have a higher oxygen affinity than adult ones.
The pH of fetal red blood cells is higher than adult red blood cells.
WRN, a REQ helicase
The data obtained with isolated mitochondria suggest that the mitochondria were uncoupled.
The most likely site of the defect is a cytochrome.
The data obtained with isolated mitochondria sugest that the patient has an inability to transfer electrons from succinate to CoQ.
The most likely site of the defect is an Fe-S center in complex I in the electron transport chain.
The presence of lactic acidemia suggests a problem at the level of pyruvate metabolism.
Creates and reseals double-stranded breaks in double-stranded DNA.
Regulates the level of superhelicity of DNA in cells
Introduces negative supercoils into linear DNA molecules.
Requires ATP hydrolysis to complete its reaction.
Bacterial DNA gyrase is one type of DNA topoisomerase I
Loss of helicase activity which causes epithelial sloughing and plugging of the airways
Increased Single Strand Breaks which make epithelial cells more susceptible to bacterial toxin
Base-pair Mismatching which affects tracheal mucus production
Double-Strand breaks that persist during B and T cell differentiation which lead to immunodeficiency
UCP (uncoupling protein) molecules are found in mitochondria in BAT, but not in skeletal muscle mitochondria
When people are kept in a cool room, the activity of their BAT increases
Shivering generates heat through BAT.
BAT is a heat generating and not an energy generating tissue
In people, BAT has been found to be most active in newborns but also present in adults
45% of the curve lies below (to the left) of a Z value of 1.65
95% of the curve lies below (to the left) of a Z value of 1.65
This is the appropriate Z score for a two tailed test with alpha=.05
A Z value of 1.60 corresponds to a P value of 0.45
A Z value of 1.65 corresponds to a P value of 0.45
The shuttle is limited by the concentration of transaminases
Cytoplasmic and mitochondrial forms of malate dehydrogenase are necessary for this shuttle
Another name for this is the glycerol 3-phosphate shuttle
In this shuttle mechanism, either 2 or 3 ATP molecules will be generated for every NADH generated by glycolysis, depending on the conditions
The shuttle only operates when the NAD+: NADH ratio is higher in the cytoplasm than in the mitochondrial matrix
The sequence D-V-R-F-K-I would be likely to be found in a beta strand of a parallel beta sheet, such as element A.
Substitution of I with D in element A would be expected to destabilize the protein by disrupting the hydrophobic core.
The loop connecting beta strand C to alpha helix D is expected to be composed primarily of hydrophobic amino acid residues.
Substitution of K with R on the exposed surface of element D would be expected to destabilize the protein by altering its net charge.
The sequence D-V-R-F-K-I would be likely to be found in an amphipathic helix such as element D.
The substitution of isoleucine -> glutamate on the hydrophobic face of an alpha helix.
The insertion of one additional hydrophobic amino acid into the middle of a beta strand of an anti-parallel beta sheet.
The substitution of Met -> Leu in the middle of a beta strand of an anti-parallel beta sheet.
The substitution of Ala -> cis-Pro within the middle of an alpha helix.
The substitution of cis-Pro -> His within a turn at the surface of a protein.