Biology

Cells of elder pith

Detection of microorganisms in air

Staining of bacteria preparations

Membrane filter method

Proof of the effect of antibiotics and chemotherapeutics

Proof of the effect of disinfectants

End products of alcoholic fermentation

Propagation of sound

Merging frequency and upper hearing threshold

Sound perception and sound level measurement

Determination of the preferential temperature

Temperature and heart rate

Detection of accommodation with an optometer

Principle

When looking through a slide with two very small holes located very close together (optometer aperture), in the absence of accommodation relative to their distance, objects close to the eye appear to be relatively well focussed except that there appear to ...

Spectral colour splitting and recombination to white light

Subjective colour mixing with the colour wheel

Principle

If a circular disc separated into various differently coloured sectors is rotated by a motor so fast that the eye can no longer distinguish the colours, a mixed colour is then perceived. By varying the composition and size of the sectors, it is possible to give the ...