Question 2
Which of the following statements is FALSE
A. In a Type I reaction, a free radical undergoes a reaction with singlet
oxygen.
B. Ground state oxygen exists in the triplet state.
C. In a Type II reaction singlet oxygen reacts with a drug molecule resulting
in a peroxide.
D. Molecules in a singlet excited state may return to the ground state via
fluorescence or internal conversion.
E. All of the above are false.
Question 3
Ibuprofen (I) is less likely to cause phototoxic reactions than many other nonsteroidal anti-inflammatory drugs (NSAIDS) because
CH3
CH
COOH
C4H9
(I)
Question 1
Drugs that are likely to cause photosensitising reactions commonly have the
following structural features
A.
B.
C.
D.
E.
Planar, polycyclic stabilised resonance structures.
Absorb UV radiation below 290 nm.
Low molecular weight.
A and C are correct.
A, B and C are all correct.
A. It does not contain a branched propionic acid group.
B. Its maximal UV absorbance occurs at 265 nm.
C. Its maximal UV absorbance occurs at 310 nm.
D. It has an internal conversion mechanism allowing it to dissipate energy.
E. None of the above are correct.
Question 4
Which of the following answers is INCORRECT. An ideal sunscreen has which of
the following properties
A.
B.
C.
D.
E.
Large molar absorbtivity
Absorption at greater wavelengths between 280-360 nm
Photochemically reactive
Water insoluble
B and C are both correct
Question 5
Treatment of jaundiced babies with UV radiation causes a drop in bilirubin serum
levels because
A. the trans form of bilirubin absorbs UV radiation at 450 nm and isomerizes
to the more soluble cis form which is able to form intermolecular Hbonds with water.
B. the cis form of bilirubin absorbs UV radiation at 400 nm and isomerizes
to the more soluble trans form which is not able to form intermolecular
H-bonds with water.
C. the cis form of bilirubin absorbs UV radiation at 450 nm and isomerises to
the more soluble trans form which is able to form intermolecular Hbonds with water.
D. the cis form of bilirubin absorbs UV radiation at 400 nm and isomerises to
the more soluble trans form which is not able to form intermolecular Hbonds with water.
E. None of the above are correct.
Question 6
An ideal drug used in photodynamic therapy has which of the following
characteristics
A.
B.
C.
D.
E.
Absorb Radiation between 650-800 nm.
Have selective uptake in to tumour cells over healthy cells.
Consist of a mixture of isomers.
Rapidly undergo photobleaching.
A, B and D are all correct.
Question 9
In relation to the scheme below
O
O
OH
-thujone
7-hydroxy- -thujone
Metabolism of -thujone in the brain to give 7-hydroxy--thujone results in
A.
B.
C.
D.
E.
toxification
a less toxic metabolite
a phase 2 metabolite
hydroxyl conjugation
a non-toxic metabolite
Question 9
The cell cycle consists of the following phases: G1, S, G2, and M. Mitosis occurs
during:
A. G1
B. S
C. G2
D. M
E. Both G1 and G2
Question 10
6-Mercaptopurine (6-MP):
A. is an antimetabolite that starves the cell of pyrimidine bases
B. is an antimetabolite that starves the cell of purine bases
C. inhibits thymidylate synthetase
D. converted in vivo by hypoxanthine-guanine phosphoribosyltransferase to
6-MPMP
E. Both B. and D.
Question 11
Which of the following statements is incorrect? Cisplatin:
A. was discovered by accident - released from platinum electrode during
electrolysis induced inhibition of E. coli proliferation
B. is a platinum complex containing two ammonia molecules and two
chloride atoms in a cis configuration
C. is a platinum complex containing two ammonia molecules and two
chloride atoms in a trans configuration
D. readily forms guanine-adenine cross-links on DNA
E. reacts with nucleophilic sites such as nucleic acids and proteins
Question 12
Which of the following statements is incorrect? Gram-positive bacteria:
A. have an internal pressure of 6 atmospheres
B. have an internal pressure of 20 atmospheres
C. excrete β-lactamases
D. display more β-lactamase-mediated resistance than the Gram-negative
species
E. Both A. and D.
Question 13
Question 17
Vancomycin inhibits bacterial protein synthesis by:
A. preventing the binding of the amino-acid containing end of the
aminoacyl tRNA to the acceptor site on the 50 S in an irreversible
manner
B. preventing the binding of the amino-acid containing end of the
aminoacyl tRNA to the acceptor site on the 50 S in a reversible manner
C. binding to the D-ala-D-ala residues via five hydrogen bonds
D. reversibly binding to the 30 S bacterial ribosome to prevent access of
aminoacyl tRNA to the acceptor site
E. irreversibly binding to the 30 S bacterial ribosome to prevent access of
aminoacyl tRNA to the acceptor site
Question 14
Antimicrobial effects can be achieved with the use of agents that affect nucleic
acids, such as:
A. the rifamycins, which inhibit DNA-dependent RNA polymerase
B. the aminoglycosides, which inhibit DNA-dependent RNA polymerase
C. the rifamycins, which inhibit gyrases
D. the sulphonamides, which inhibit gyrases
E. the quinolones, which inhibit DNA-dependent RNA polymerase
Question 15
p53:
A.
B.
C.
D.
E.
is a tumour suppressor gene – absence can lead to cancer
inhibits apoptosis in cells that have undergone DNA damage
is an oncogene – presence can lead to cancer
is a tumour suppressor gene – presence can lead to cancer
p53 acts as a “checkpoint" to promote cell growth if damage is detected
Question 16
Amantadine is effective against:
A. Influenza A
B. Influenza B
C. Influenza C
D. A. and B are correct
E. A, B and C are correct
What endogenous compound is the structure of Lamivudine (3TC) most similar
to?
A. Deoxycytidine
B. Deoxythymidine
C. Deoxyadenosine
D. Deoxyguanosine
E. Deoxyinosine
Question 18
A functional group required for Indinavir’s activity is:
A. 4-Amino
B. Proline
C. Acetoamido
D. Phenylalanine
E. Azide
Question 19
Which of the following statements is correct? Stavudine (D4T) directly:
A. Inhibits the synthesis of viral DNA
B. Inhibits the penetration of the virus into the host cell
C. Inhibits the viral translation process
D. Interferes with the assembly of viral proteins
E. Inhibits the spread of the viral infection from the host cell
Question 20
Which of the following statements is correct? Oseltamivir phosphate:
A. prevents the virus from exiting the host cell by blocking the cleavage of
the terminal sialic acid from the virus
B. prevents the virus from exiting the host cell by blocking the cleavage of
the terminal sialic acid from the host cell
C. is orally in-active, and has a 5-membered ring structure
D. is orally in-active, and has a 6-membered ring structure
E. is not specific for viral neuraminidase
Question 21
Which of the following statements is correct? Cidofovir:
A.
B.
C.
D.
E.
is selective for viral thymidine kinase
is a prodrug converted to cidofovir monophosphate
is an oral prodrug requiring metabolic conversion to its active form
preferentially inhibits viral DNA polymerase
is a guanosine analogue