We have developed a 9-week undergraduate laboratory series focused on the purification and characterization of "Thermus aquaticus" DNA polymerase (Taq). Our aim was to provide undergraduate biochemistry students with a full-semester continuing project simulating a research-like experience, while having each week's procedure focus on a single…

A new method is introduced to study the behaviour of the falling spherical ball in a viscous liquid using the well known Stokes' law. Experimental results are compared with those obtained by numerical calculations. Upper limits on the size and mass of the spherical balls of different materials used in the experiment are presented. (Contains 5…

An awareness of the extensive diversity of living organisms is an essential component of a complete biology education. It is important for students to explore the spectacular variety of living things as well as to understand the many solutions to the challenges of living on Earth that have evolved in different organisms. The "National Science…

Cell signaling is an essential cellular process that is performed by all living organisms. Bacteria communicate with each other using a chemical language in a signaling pathway that allows bacteria to evaluate the size of their population, determine when they have reached a critical mass (quorum sensing), and then change their behavior in unison…

An undergraduate organic chemistry experiment demonstrating real-life application of GC-MS to arson accelerant identification is described. Students are given the task of comparing a sample recovered from a "crime scene" to that from a "suspect's clothing". Accelerants subjected to different conditions are recovered using a quick and simple…

Liquid 2-chlorobenzaldehyde was converted, by grinding with potassium hydroxide pellets, into equimolar quantities of solid 2-chlorobenzoic acid and solid 2-chlorobenzyl alcohol in a Cannizzaro reaction. TLC, IR, and NMR experiments, using authentic samples for comparison, confirmed the identity and purity of the two products. Guided-inquiry…

A novel undergraduate chemistry experiment involving superabsorbent polymers commonly used in diapers and other personal care products is described. Students observe the removal of divalent transition-metal ions from aqueous solutions by the polymers. With the procedures provided, students are able to color the superabsorbent polymers with metal…

This article describes the construction of an inexpensive, robust, and simple hydrogen electrode, as well as the use of this electrode to measure "standard" potentials. In the experiment described here the students can measure the reduction potentials of metal-metal ion pairs directly, without using a secondary reference electrode. Measurements…

The learning outcome of a physics laboratory course for medical students was examined in an interdisciplinary field study and discussed for the electrical physiology ("Propagation of Excitation and Nerve Cells"). At the Ludwig-Maximilians-University of Munich (LMU) at a time about 300 medicine students were assessed in two successive…

Many general physics laboratories involve the use of springs to demonstrate Hooke's law, and much ado is made about how this can be used as a model for describing the elastic characteristics of materials at the molecular or atomic level. In recent years, the proliferation of computers, and appropriate sensors, have made it possible to demonstrate…

The traditional range of marine microcosm laboratory experiments is presented as an ideal environment to teach the entire analysis process. The microcosm lab provides student-centered approach with opportunities for collaborative learning and to develop critical communication skills.

Students should understand both the science and the engineering models of experimentation. Since students are often predisposed to using the engineering model, teachers must intentionally design activities that better reflect the nature of scientific experimentation. In this article, the authors recommend some guidelines that can be used when…

We consider a simple oscillator that exhibits harmonic and anharmonic regimes and analyse its behaviour over the complete range of possible amplitudes. The oscillator consists of a mass "m" fixed at the midpoint of a horizontal rope. For zero initial rope tension and small amplitude the period of oscillation, tau, varies as tau is approximately…

A straightforward and inexpensive laboratory experiment is presented that investigates the physiological stress response of zebrafish after a 5 degree C increase in water temperature. This experiment is designed for an undergraduate physiology lab and allows students to learn the scientific method and relevant laboratory techniques without causing…

In this paper we analyse the behaviour of a small-scale model of a magnetic levitation system based on the Inductrack concept. Drag and lift forces acting on our prototype, moving above a continuous copper track, are studied analytically following a simple low-speed approach. The experimental results are in good agreement with the theoretical…