Here are several practice problems…
- Identify
the hybridization and bond angles for each carbon, oxygen, and nitrogen
atom in the following molecules
- Tyrosine
at physiological pH.
- Acetylcholine
- Norepinephrine
- An
enzyme catalyzes reaction rates by lowering a reaction’s activation
energy. Calculate by what factor the
reaction rate increases for an enzyme-catalyzed reaction with an activation energy of 20 kJ/mol compared with the rate
when no catalyst is present and the activation energy is 100 kJ/mol.
- Phosphoric
acid has pKa’s of 1.97, 6.82, and 12.5.
- Draw
the complete Lewis structures for the two most concentrated forms at a
physiological pH of 7.4.
- Calculate
the exact relative amounts of these two forms at a pH of 7.4.
- Draw
the mechanism for the reactions that occur among phosphate, ethanolamine,
and glycerol to form a part of a phospholipid structure
often found in cell membranes.
- A
recent study demonstrated that the replacement of a carboxylic acid group
with a phosphonic acid provided increased
acidity while also lowering the log P value. The presence of phosphonic acid functionalities in several marketed
drugs demonstrates the utility of this approach. One of the phosphonic
acid substituted compounds being examined exhibited a log P value of 1.22.
Calculate the volume of 1-octanol
required to extract 99% of the moles of this substance out of 1.0 liters
of water.
- Eukaryotic
cell membranes have chloride concentrations of 110 mM
and 5 mM across cell membranes.
- Calculate
the Nernst potential, draw a diagram, and
clearly explain what the Nernst potential
physically represents.
- Draw
the complete molecular structure of the GABA neurotransmitter at
physiological pH and explain what happens when a GABA receptor is
activated. Identify several
substances that activate GABA receptors.
- Diagram
how potential energy changes as the aspartic acid side group approaches
the nitrogen end of acetylcholine. Draw the structures and show the nature
of this interaction.
- Drugs
A, B, and C have ED50’s of 3 nM, 6 mM, and 0.001 mM
respectively. Substance A has twice
the efficacy of B and one-third the efficacy of C. Draw a dose response diagram that
clearly shows the relative potencies and efficacies of these substances on
a given target.