Mutational inactivation of a specific gene is the most powerful technique to analyze the biological function of the gene. This approach has been used for a long time in viruses, bacteria, yeast, and fruit fly, but looked quite hopeless in more complex organisms. Targeted inactivation of specific genes (also known as knock-out mutation) in mice is…

To promote understanding of the authority of the primary literature in students taking our biochemistry laboratory courses, a biochemistry laboratory exercise on the determination of an acceptable molar absorptivity value of 2-nitrophenol (2-NP) was developed. This made the laboratory course much more relevant by linking to a thematic thread,…

Laboratory exercises, which utilize alkaline phosphatase as a model enzyme, have been developed and used extensively in undergraduate biochemistry courses to illustrate enzyme steady-state kinetics. A bioinformatics laboratory exercise for the biochemistry laboratory, which complements the traditional alkaline phosphatase kinetics exercise, was…

A simple experimental set-up to study free and forced convection in undergraduate physics laboratories is presented. The flat plate of a domestic iron has been chosen as the hot surface, and a hairdryer is used to generate an air stream around the plate. Several experiments are proposed and typical numerical results are reported. An analysis and…

Biodiesel was produced by transesterification of waste olive oil with methanol and Novozym [R] 435. The effect of the molar ratio of methanol to triolein, mode of methanol addition, reaction temperature, and mixing speed on biodiesel yield was determined. The effect of different acyl acceptors and/or solvents on biodiesel yield was also evaluated.…

The Robinson annulation is a topic of importance in the second-year organic curriculum. A one-pot, enantioselective Robinson annulation is described. The experiment is completed in two lab periods and is geared towards the second-year organic chemistry major. To our knowledge, this is the first example of a one-pot enantioselective Robinson…

An experiment is described involving the nitration of ortho or meta monosubstituted benzoic acids (XC[subscript 6]H[subscript 4]CO[subscript 2]H, X = Halogen, Me, OH, or OMe) and monochlorinated acetanilides with nitric acid to determine the regioselectivity of addition by [superscript 1]H NMR spectroscopy and molecular modeling. Students were…

This experiment describes the synthesis of gentisyl quinone isovalerate, or blattellaquinone, a sex pheromone of the German cockroach that was isolated and identified in 2005. The synthesis is appropriate for the second semester of a second-year organic chemistry laboratory course. It can be completed in two, three-hour laboratory periods and uses…

A sorption experiment using a gas chromatograph is described that can help students understand the "molecular-shape selectivity" behavior of zeolites in the subnano regime. Hexane isomers are used as probe molecules to demonstrate the sorption phenomena. In the experiment, a zeolite adsorbs certain hexane isomers with molecular sizes smaller than…

The speed of sound is measured in several gases using a pulsed laser to create a micro-spark on a carbon rod and a microphone connected to a digital oscilloscope to measure the time-of-flight of the resulting shockwave over a known distance. These data are used to calculate the heat capacity ratios (C[subscript p]/C[subscript V]) of the gases and…

A simple student experiment investigating dependence on air pressure of the attenuation of alpha particles in air is described. An equation giving the pressure needed to absorb all alpha particles of a given energy is derived from the Bethe-Bloch formula. Results are presented for the attenuation of alpha particles from americium 241 and radium…

The restoration of wolves to Yellowstone National park after a 7-year absence created a natural experiment on the ecological effects of top predators. In this activity, students use mathematical models to explore how carrion from wolf kills can reduce negative effects of climate change on scavengers in the park.

In order to demonstrate how plants remove water from the soil and release it to the atmosphere, students compared open- and closed-growing systems using drought-tolerant and higher water requirement plants. Then, students designed a drought-tolerant garden demonstrating what they had learned. Through this experience, students not only learned…

In this paper, a simple MATLAB-based PC program that enables the computer to function as a replacement for the electronic scalar-counter system associated with a Geiger-Muller (GM) tube is described. The program utilizes the ability of MATLAB to acquire data directly from the computer sound card. The signal from the GM tube is applied to the…

The physics laboratory has long been a distinctive feature of physics education. It has been given a central role in the teaching and learning of physics at school and undergraduate levels in universities. The literature indicates that science educators have suggested that there are academically rich benefits in the learning and understanding of…