This study reports on the theoretical- and empirical-based design and evaluation of cell membrane biology learning activities within the Model of Educational Reconstruction and experiential realism. First, we designed analogy-based learning activities by considering students' and scientists' conceptions as described in the literature. Secondly, we…

Flow cytometry has become an important tool in the fields of veterinary, medicine, and biological sciences in general. However, in the introductory and even in advanced university degree courses, students do not have many opportunities to be in contact with this type of technology. This situation motivated us to design a simple and inexpensive…

In recent years the possibility of observing by microscopy the dynamic activity of living cells has been largely pursued. We have developed a low-cost (~ 260 euros) on-stage cell incubator for inverted optical microscopes. This device allows to keep cells in good conditions for their survival and proliferation. The device is based on the use of…

The attractive photophysical properties of luminescent nanoparticles have prompted numerous studies on their synthesis and biological applications. Due to the complexity of components, sizes, morphologies, and strong light scattering of the nanoparticles the absorption spectrum alone is not enough for characterising and analysing the real…

Programmed cell death, or apoptosis, is a cellular pathway by which individual cells self-destruct for the benefit of the organism. In this practical paper, we describe laboratory exercises with an inquiry-based learning (IBL) approach in which undergraduate students compared apoptosis among different types of cultured cells. Ultraviolet (UV)…

All the cells of higher organisms have the same DNA but not the same proteins. Each type of specialised cell that forms a tissue has its own pattern of gene expression and, consequently, it contains a particular set of proteins that determine its function. Here, we describe a laboratory exercise addressed to undergraduate students that aims to…

Introducing research in undergraduate biology studies may contribute to creating research vocations and generate the idea that science may influence all aspects of common life. However, laboratory practices are too often disconnected from current investigations and rarely address real-life questions that are really interesting for students.…

The microbial growth curve is widely studied within microbiology classes and bacteria are usually the microbial model used. Here, we describe a novel laboratory protocol involving flow cytometry to assess the growth dynamics of the unicellular microalgae "Isochrysis galbana." The algal model represents an appropriate alternative to…

The effects of impeller size, agitation and aeration on the rate of yeast growth were investigated using bench-top bioreactors. This exercise, carried out over a six-month period, served as an effective demonstration of the importance of different operating parameters on cell growth and provided a means of determining the optimisation conditions…

This paper reports on a simple hands-on laboratory procedure for high school students in studying both radiation damage and DNA repair systems in bacteria. The sensitivity to ultra-violet (UV) radiation of both "Escherichia coli" and "Serratia marcescens" is tested by radiating them for varying time periods. Two growth temperatures are used in…

Describes a method for in vitro culturing of cells from amphibian early embryos. Such cells can be used to demonstrate such properties of eukaryote cells as cell motility, adhesion, differentiation, and cell sorting into tissues. The technique may be extended to investigate other factors. (Author/JN)

A simple method of studying thyroxine-induced resorption of tadpole tails in vitro is described. This procedure demonstrates that resorption is dependent on thyroxine and requires protein synthesis. It introduces students to the use of tissue culture methods. (Author)

Thin slices of potato can be used to demonstrate the presence of protein, carbohydrates, and nucleic acids at the cellular level. Procedures and materials are provided for these simple tests. Also indicates that the presence of fat can be readily seen by staining avocado with Sudan red or Sudan black. (Author/DH)

Cell death is an essential factor in many biological processes including development. Discusses two types of cell death: (1) necrosis (induced by sodium azide); and (2) apoptosis (induced by sodium chromate). Illustrates key features that differ between these two types of cells death including loss of membrane integrity and internucleosomal DNA…

Actin and myosin have now been demonstrated to be important constituents of many eukaryotic cells. Their role is primarily that of a contractile system underlying all aspects of cellular motility. Described here is a simple experimental system to demonstrate quantitatively aspects of motility and its regulation in a slime mold. (Author/MA)