The author undertook the experiments on the effect of light on seed germination. It was revealed that the seed of Plantago virginica L. was light sensitive. The germination was promoted by irradiation with red light (about 650nm) but was not with blue light (450nm) and far-red light (700nm). The results suggested that phytochrome took part in the germination of the seeds. The seeds after hervest from field were dormant and required the period of after-ripening for germination. These observations contribute to better understanding of students for plant life and light action.

Most of biological experiments on photosynthetic pigments in upper secondary school are limited to their separation by paperchromatography. In this study, I tried to develop teaching materials for students to find the diversity of photosynthetic pigments among plants and infer the process of the evolution from algae to seed plants, through the separation of photosynthetic pigments and observation of their absorption spectra.

Plant materials for this research were Schefflera arboricola (Seed plant), Ulva pertusa (Chlorophyta), Undaria pinnatifida (Phaeophyta), Porphyra yezoensis (Rhodophyta). To improve the extractive efficiency of photosynthetic pigments, the algae were dried in the dark for about half day. The plant materials were ground with powder of dried silica gel. The fat-soluble photosynthetic pigments were extracted with diethyl ether, while water-soluble pigments were extracted with 10% NaCl solution. Then, fat-soluble photosynthetic pigments were analyzed by TLC using silica gel aluminum plate. Their absorption spectra were observed by a devised simple apparatus. Using this apparatus, the spectra were observed as dark line (region). Separated pigments (Chl.a, Chl.b, fucoxanthin, phycobiliprotein) showed their characteristic absorption spectra. A series of this experiment is very useful for students to find the diversity of photosynthetic pigments among various plants and to relate it to the plant evolution from algae to terrestrial seed pants.

Now, investigations are carried out by observing of contractile vacuoles of Paramecium and changes in external osmolality. For over 40 years, NaCl has been used for the control of external osmolality.

In this study, it was found that, using NaCl, the results did not follow the idealized models, but nonelectrolytes, such as sucrose, were suitable.

It was assumed that NaCl was not appropriate for investigations because of the possibility that Paramecium cells cause an influx and efflux of Na+. On the other hand, the assimilation of sucrose by Paramecium cells can be ignored. In conclusion, we should use nonelectrolytes such as sucrose for the control of external osmolality, but not NaCl.

Upon exposure to hyperosmotic environments, e.g. 100mM sucrose, the Paramecium cells immediately shrank and the contractile vacuoles ceased their activities. After 1 hour, the cells swelled near to their initial size and shapes and contractile vacuoles resumed their functions. This indicates that the cells adapt to hyperosmotic stress. Thus it is possible for students to investigate the response of Paramecium to hyperosmotic and hypoosmotic stress in sim­ ple experiments.

In Victoria, the Victorian Certificate of Education (VCE) is most common among certificates required to apply any tertiary institute in the Victoria State. Thus, the number of students who take the VCE course is larger than other courses in senior secondary schools. VCE Biology is one of the subjects in natural science area. The subject consists of 4 units: Unit 1 is ecology ori­ ented, Unit 2 is cell biology oriented, Unit 3 is physiology and developmental biology oriented, and Unit 4 is systematics, genetics and evolution oriented. One of the distinctive features of the VCE Biology is its assignment. Three or four tasks are prepared in each unit of the subject. In order to complete the assignment, students should carry out some laboratory work, field studies and investigations to collect data and information from a number of sources. They also need to analyze data to write some reports. In Unit 3 and 4, Com­ mon Assessment Tasks (CATs), which include writing report and paper test, are prepared. Another distinctive feature of the curriculum is that there are some applied biological aspects in the contents of each unit.