In this teaching laboratory, the students are directed in an exercise that involves designing and performing an experiment to determine estrogen's role in regulating delayed implantation (diapause) in female rats. To encourage active participation by the students, a discussion question is provided before the laboratory exercise in which each…

A laboratory experiment is described that extracts the tetrapyrrolic teal-colored biliverdin IXa, as its dimethyl ester, from commercially available emu eggshells. The extraction of ~10 mg samples of biliverdin is simple and requires two 3 h lab periods: A two-step acid digestion and liquid-liquid extraction, followed by short silica gel flash…

Science popularisation festivals attract more and more people every year, showing that there is a need to satisfy public curiosity. Such events are good occasions to disseminate knowledge to a large audience. The results of scientific research bring advances for mankind. Since research mostly depends on public funds, it is important to gain…

This investigative laboratory activity engages students in observing, recording, graphing and analyzing pulsation rates in a commonly used laboratory organism, blackworms. This activity stresses how various drugs can impact the pulsation rate in blackworms at varying concentrations. In addition, we have incorporated two new ways to view the…

Students are introduced to spectrophotometry in comparing the antioxidant activity of pure eugenol and oil of cloves from a commercial source using a modified ferric reducing antioxidant power (FRAP) assay. The extraction of the essential oil from dried cloves is demonstrated to facilitate discussions on green chemistry. The anesthetic properties…

Diverse communities of arthropods and microbes provide humans with essential ecosystem goods and services. Arthropods are the most diverse and abundant macroscopic animals on the planet, and many remain to be discovered. Much less is known about microbial diversity, despite their importance as free-living species and as symbionts. We created…

Embryonic development offers a unique perspective on the function of many biological processes because of embryos' heightened sensitivity to environmental factors. This hands-on lesson investigates the effects of elevated vitamin A on the morphogenesis of chicken embryos. The active form of vitamin A (retinoic acid) is applied to shell-less (ex…

A concurrent-chains procedure was used to examine choice between segmented (two-component chained schedules) and unsegmented schedules (simple schedules) in terminal links with equal inter-reinforcement intervals. Previous studies using this kind of experimental procedure showed preference for unsegmented schedules for both pigeons and humans. In…

Zebra finch song behavior is sexually dimorphic: males sing and females do not. The neural system underlying this behavior is sexually dimorphic, and this sex difference is easy to quantify. During development, the zebra finch song system can be altered by steroid hormones, specifically estradiol, which actually masculinizes it. Because of the…

This lesson can be used at the beginning of the year to teach students how to conduct inquiries using the essential features described in "Inquiry and the National Science Education Standards" (NRC 1996). The lesson is divided into several activities which may be spread over several days or interspersed with your other beginning-of-the-year…

Describes methods for studying the direct effect of thyroid hormones on the induction of metamorphic change in amphibians. (CS)

Describes methods for studying heart primordia of the chick embryo, using the organ culture method. (CS)

Dilated canine hearts were used to teach undergraduate students internal and external cardiac anatomy. The specimens were dilated using hydrostatic pressure and then fixed using 5% formalin. These specimens provided the students with an alternative to prepackaged embalmed hearts and anatomical models for studying the external and internal cardiac…

This book presents essential learning approaches. It introduces educational and training activities, as well as various innovative methods aiming at the development of practical skills, in order to strengthen the continuous process of environmental education, and in particular the education for sustainable development (ESD). In doing so, it…

Modern low-cost data acquisition systems enable pupils to study the voltage-current characteristics of a wide range of different materials and devices in a quick and convenient way. In particular, it is possible to study materials, such as meat and vegetables, not normally associated with school physics experiments.