2015 biochem Flashcards
What is the change that occurs in prion disease?
A. Increased beta sheets
B. Increased alpha helices
A. Increased beta sheets
Which structure level is altered in prion disease? A. Primary B. Secondary C. Tertiary D. Quaternary
B. Secondary
The deletion of Phe508 in cystic fibrosis affects what?
The ATP binding domain
A protein was mutated to lack a signal peptide. What can be assumed about this protein?
It was synthesized on free ribosomes
An antibiotic blocks the 30s ribosomal subunit. Which part of the translation will be affected? A. Elongation B. Initiation C. Translocation D. Termination
A. Elongation
I think its B
An antibiotic that inhibits translocation results in a peptide that’s
A. Shorter
B. Longer
A. Shorter
Citrate was exported from the mitochondria into the cytosol. What will this transport stimulate?
A. Lipogenesis
B. Glycolysis
C. Lipolysis
A. Lipogenesis
Which transporter in the electron transport chain can carry two electrons and donate one at a time?
A. Coenzyme Q
B. Cytochrome C
A. Coenzyme Q
Which enzyme is targeted in treating gout?
Xanthine Oxidase (which makes uric acid)
What is the effect of prolonged trans-fat consumption?
A. Suppressing the activity of LDL receptors
B. Increasing the activity of LDL receptors
C. Higher HDL levels
A. Suppressing the activity of LDL receptors
What is the principal product of glycogen breakdown in muscles? A. Glucose B. UDP-Glucose C. Glucose-1-phosphate D. Maltose
C. Glucose-1-phosphate
What causes Alzheimer disease?
A. Increased beta sheets
B. Deoxygenated valine beta hemoglobin
C. Incorrect cleavage of Amyloid Protein Precursor
C. Incorrect cleavage of Amyloid Protein Precursor
Which bond is not broken if a protein is cooked?
A. H-bond
B. Electrostatic bond
C. Peptide bond
C. Peptide bond
What does a deficiency in vitamin C impair?
Hydroxylation of proline
What does an allosteric effector do?
A. Stabilize the protein configuration
B. Bind to the active site
C. Alters the stability of the protein through covalent modifications
A. Stabilize the protein configuration
If we add 0.1 mM of a noncompetitive inhibitor to a sample where the Kmwas 0.5 and Vmax was 20, what is correct regarding km and Vmax after this whole process? A. vmax = 20, km = 5 B. vmax = 10, km = 0.5 C. vmax = 30, km = 2.5 D. vmax = 20, km = 0.5
B. vmax = 10, km = 0.5
Which lipase requires a colipase to function? A. Pancreatic lipase B. Phospholipase C C. Hepatolipase D. Hormone sensitive lipase
A. Pancreatic lipase
Which of the following is the product of the rate-limiting step of cholesterol synthesis? A. Acetoacetyl coA B. HMG CoA C. Mevalonic acid D. IPP
C. Mevalonic acid
Where in a cell, do desaturase reactions take place? A. Golgi Apparatus B. Mitochondria C. Nucleus D. Endoplasmic Reticulum
D. Endoplasmic Reticulum
What causes acidosis in prolonged starvation? A. Ketone bodies B. Acetone C. Gluconeogenesis D. Fatty acid oxidation
A. Ketone bodies
In what way does the pentose phosphate pathway aid antioxidants?
A. Converts ribulose-5-P to ribose5-5-phosphate
B. Keeps glutathione in a reduced state
B. Keeps glutathione in a reduced state
Which of the following drives the movement of H from the matrix into the intermembrane space? (diagram)
A. Concentration gradient
B. Electrochemical gradient
C. ATP hydrolysis
D. Energy of the redox reactions from ETC
D. Energy of the redox reactions from ETC
Philadelphia chromosome is associated with which caner?
Chronic Myeloid Leukaemia
What is the function of a deacetylation reaction?
reduces gene expression.
What is the function of a deacetylation reaction?
reduces gene expression
Which of the following is a spontaneous cause for DNA mutation?
A. Tautomerization
B. UV irradiation
C. Metabolism that produces ROS
A. Tautomerization
What reaction is catalyzed by superoxide dismutase?
O2 + 02 -> h2O2
Which of the following should a patient with carnitine 1 deficiency avoid?
A. Long chain fatty acids
B. FA<12C
A. Long chain fatty acids
What does a-amantin inhibit?
A. RNA polymerase II
B. RNA polymerase I
C. RNA polymerase III
A. RNA polymerase II
Which of the following contains a primase?
A. DNA polymerase B
B. DNA Polymerase alpha
C. DNA Polymerase Y
B. DNA Polymerase alpha
What is the annealing temperature for this DNA sequence:
5-ACA CAG ATA CAG ATA GCT-3
2(#A and T) + 4(# C and G)= 2 X 11 + 4X7= 50C
Diagram of fructose pathway in glycolysis. What action of fructose can potentially cause liver damage?
A. lack of regulation by phosphofructokinase1
B. Aldolase B deficiency
C. DHAP accumulation
A. lack of regulation by phosphofructokinase1
Which of the following enzymes is affected by Nag?
Carbamyl synthase
Which of the following is a source for ammonia in the urea cycle? A. Aspartate B. Glutamine C. Glatamate D. Alanine
B. Glutamine
