Problem 1: Half a mole of glucose is dissolved in 1 kg of water. Which answer is closer to the extra osmotic pressure associated with the addition of glucose on glucose-impermeable vesicles in the same mixture? The glucose molecules are not ionized or changed in solution.
Answers:

• 0.8 atm
• 0.01 atm
• can't tell without MM of glucose
• 12.7 atm
• 83 N/m2
• 12 Pa

Problem 2: The freezing point of blood serum is about -0.56 °C. What happens if a saltier sea water (with a larger freezing point depression of T_f = -1.8 °C ) is added to red blood cells culture? (Hint: freezing point depression below 0°C depends linearly on the osmolarity of solution)
Answers:

• impossible to say without knowing molecular masses of the constituents of blood and sea water.
• blood cells shrink
• blood cells swell up and birst
• blood cells preserve their volume

Problem 3: IC50 for drug binding similar to the dissociation constant K_d and measures concentration at which 50% of the receptor function is suppressed. The binding free energy is proportional to the following function of the IC50 concentration:
Answers:

• Log(IC50)
• e^-IC50
• IC50²
• (IC50)^-½
• IC50

Problem 4: Calorimetric data on binding of several anti-HIV drugs to their common target, HIV protease, is given in the table (all values in kcal/mol reasured at 25°C). Which drug has the highest binding affinity (strongest binding)?
Answers:

• Nelfinavir
• Darunavir
• Amprenavir
• Tipranavir
• Indinavir
• Saquinavir
• Lopinavir
• Ritonavir
• Atazanavir

Problem 5: Proton-rich isotopes may decay via positron emission and this property is used in fluorine-18 based PET techniques. Each electron-positron annihilation produces two 511 keV photons. What is the wavelength of those photons? Find the closest answer. Equations needed: f x λ = c (1); E = h x f (2). where: f = frequency in Hertz (Hz = 1/sec) , λ = wavelength in meters (m), c = the speed of light (299,792,458 m/s), E = energy in electron Volts (eV), h = Plank's constant (6.626068*10^-34 J s), (Hint: solve (2) for frequency, then solve (1) for &lambda )
Answers:

• 3.6x10¹² m
• 3 nM
• ~2.4 pm
• can not tell without knowing the frequency

Problem 6: When quoting the energy of the PET photons due to 18-fluorine decay as 511 keV, we mean the energy of
Answers:

• two photons
• all answer choices are correct because they mean the same quantity
• a single photon
• an Avogadro number of photons

Problem 7: The decay of I-131, the radiopharmaceutical used to treat thyroid cancer, releases energy in the form of β (~90%) and γ (~10%) radiation. The average energy release per nucleus is 192 keV for β and 364 keV for γ. Given a sample of I-131 with total activity of 100 mCi, how much energy does it emit per second in the form of γ-radiation? Give your answer in J/s or derivatives of J/s (e.g. milli, micro- etc.).
Answers:

• 21.5 J/s
• 3.7x10⁹ J/s
• 2.5 mJ/s
• 215.5 μJ/s

Problem 8: In positron emission tomography, PET, imaging, electron–positron annihilations result in pairs of 511 keV gamma photons. Order the following photons from highest to lowest energy: (UV) near ultraviolet, (IR) far infrared, (PET) PET machine, (XR) X-rays used in crystallography (λ ~ 1 Angstrom):
Answers:

• IR, UV, PET, XR
• IR, UV, XR, PET
• IR, XR, PET, UV
• XR, PET, IR, UV
• PET, XR, UV, IR

Problem 9: Most of the small molecule FDA approved drugs affect their targets in the following manner:
Answers:

• emit gamma rays to break multiple bonds in the target
• non-covalent binding to the drug binding pocket
• emit electrons to destroy the target