This resource uses a student-designed laboratory exercise as a model to demonstrate the techniques and concepts surrounding the scientific method.
Microbiology is the study of microorganisms, which are unicellular or cell-cluster microscopic organisms. This includes eukaryotes such as fungi and protists, and prokaryotes, which are bacteria and archaea. Viruses, though not strictly classed as living organisms, are also studied. In short; microbiology refers to the study of life and organisms that are too small to be seen with the naked eye. Microbiology is a broad term which includes virology, mycology, parasitology, bacteriology and other branches. Microbiology is researched actively, and the field is advancing continually. We have probably only studied about one percent of all of the microbe species on Earth. Although microbes were first observed over three hundred years ago, the field of microbiology can be said to be in its infancy relative to older biological disciplines such as zoology and botany.
In this investigation, students will become proficient in the use of integrated digital technology as they capture images of exemplary specimens with digital microscopes. Students can later use these images individually to compose and illustrate original lab manuals (digital notebooks) or in collaborative groups to design multimedia presentations. Students actively engage in their learning and participate in high levels of cognitive functioning as they construct knowledge about the phyla they are studying. The creative aspects of these exercises provide for a high interest laboratory experience that taps into intrinsic motivation and leads to student success in demonstrating content mastery.
The fungi which cause rot and decay in our forests are vital members of the ecosystem. By decomposing the hard woody stems of trees they help recycle important nutrients, minerals, and carbohydrates. Unlike many organisms which are easy to see, the fungi are often hidden under bark or within living stems and their presence is not obvious. This laboratory exercise provides instructors with information about where to find and how to visualize and manipulate fungi which cause rot and decay, while discovering how ubiquitous and important they are.
This model of the lateblight life cycle in potatoes allows students to simulate the effects of environmental variables on the <i>Phytopthora infestans</i> life cycle.
Crop scientists frequently use simulations to try to convince themselves and others of the reasonableness of a new control method. They can use simulation results to support their claims.
Lateblight allows students
* to manipulate the variables that affect the development of late blight
* to adjust the economic parameters that determine the cost-effectiveness of the disease management procedures
Students can also simulate the use of potato cultivars by altering:
* the level of resistance to the fungus
* the time of initiation of tuber production
* the yield potential of the crop in the absence of disease
This workshop demonstrates on-line use of the national electronic bulletin board, complete with electronic mail started in 1987 by the National Association of Biology Teachers. Once on-line, 14 special interest areas are available, such as AP- Biology, magazine and book reviews, ABT Journal, NABT membership services, question and answer forum, software reviews, and swap/sale of used equipment. Also available for downloading onto your computer are extensive files of labs, graphics, and handouts. Discussions of this and other databases will emphasize the power of these new professional communication tools. Note: This workshop is not included in the published proceedings volume because it was not submitted by the author.
Resistan is a mechanistic simulation model of the process of selection of fungicide-resistant biotypes of a hypothetical fungal pathogen of a hypothetical crop.
The fungus is a polycyclic organism with many generations per season. There is no genetic component in this simulator. Reproduction is assumed to be asexual. A small proportion of the initial inoculum is designated as the fungicide-resistant biotype at the start of the season, and the response of that population to various fungicide spray programs is observed as the season progresses.
Resistan can be made to simulate different fungi and different fungicides by changing the parameters that control the model.
One interesting feature of this simulation is the ability to include economic factors in the simulation. Total costs, total revenue, and profit are calculated at the end of each season based on the following parameters:
* Fungicide Cost is used in the benefit-cost analysis at the end of the simulation.
* Application Cost is the cost of a single spray application in dollars per acre. This does not include the cost of the fungicide.
* Fixed Costs are the total crop production costs, excluding the fungicide spray application cost and the cost of the fungicides.
* Maximum Revenue is the expected revenue from the crop without any losses resulting from the disease.
This laboratory focuses on some aspects of spore color determination in the fungus Sordaria fimicola. Tetrad analysis of asci from a cross between strains mutant for two spore color genes is used to determine if the genes are linked and to map the location of each gene relative to the centromere. This laboratory is logistically simple and inexpensive, the data are relatively easy to collect, and the analysis facilitates a good understanding of meiosis and Mendel's principles of inheritance. Alternate approaches to the use of this laboratory are discussed.
The Wine simulation allows you to model the fermentation process and explore variables and their effects on winemaking. Students can probe the basic fermentation process. Enhancements such increased alcohol tolerance in cultivated yeasts used in modern wine making can be explored as well.
