Developmental studies on the teaching materials of quantitative experiment in biological education.

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I intended to study on the development of teaching materials of quantitative experiment in biological education. The summary of the results is as follows:(1) Developmental studies on a growth-measuring instrument of microorganisms: The instrument is constructed with solar cell, circuit tester, simple amplifier of hand making, and circular fluorescent lamp. The growth curves of Chlamydomonas reinhardtii and Saccharomyces cerevisiae were measured using the equipment, and the results obtained were similar to those obtained photometrically using a traditional photometer. The distinguishing marks of this instrument are 1) Density of the microorganisms can be measured as growing state in culture vessel without taking out some of the suspension medium. Therefore, the aseptic manipulation and the loss of suspension medium can be eliminated. 2) Operation is simple, and it takes 1 - 2 minutes for one measurement. 3) It's inexpensive and no necessity of expert skill for construction of the equipm … More ent. 4) Large space and dark room are unnecessary.(2) Demonstration experiment using a television camera for volumetric measurement of photosynthesis and respiration: A droplet of food color solution was used as an indicator of the volumeter, and seven volumeters were imaged on the television screen. Investigators and students can get data from the screen. Seven neutral optical filters of different transmissivity were prepared for seven volumeters to measure photosynthesis rate under different light intensities at the same time. Application of this filters on the volumeter made the measurement of photosynthesis rate under different light intensity possible to compare between a sun leaf and a shade leaf within a school period.(3) Experiment for measurement the effects of sulfur dioxide on plants: Using the simple volumetric respirometer (Takaoki & Nakagishi, 1988) and the simple sulfur-dioxide fumigation method (Takaoki & Mitani, 1986), the effects of sulfur dioxide on respiration rates of germinating seeds and petals were observed. Visible injury of sulfur-dioxide fumigation on petals of morning glowry was observed even when fumigation was made three minutes. This experiment is available for children of primary school.(4) Equipment for measuring root pressure in a few minutes: This method is manometric and extremely rapid (Takaoki, 1965). The measurements using this method is very scarce. The effects of respiratory inhibitors and uncouplers on the root pressure of corn root segments were observed. It was recognized that this method is available not only for research on water absorption by root but also for education. Less