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Summary Instruction in independent scientific work is an integral part of science education that has been severely neglected in the past year due to distance teaching. Here, we present an approach in which students used everyday objects to investigate the activity of yeast as a function of temperature and substrate in subtasks at home. The results of the whole course were collected in a Google document and centrally analyzed. At the same time, the learners were asked to upload their experimental reports with photos to a wiki. This enabled an exchange of experiences among the learners and problems could be discussed publicly. Furthermore, basic skills like observing, logging and detailed reporting were practiced. Online documentation and recording of results is thus a suitable method to activate and coordinate the implementation of home experiments. [ABSTRACT FROM AUTHOR]

Summary The tricks of stinking hellebore The stinking hellebore (Helleborus foetidus) uses ingenious tricks in order to attract pollinators and to achieve the dispersal of its seeds. Yeasts metabolise sugar available in nectar und thereby warm it up to attract bees and bumble bees in cold, early spring. This remarkable heating system allows the flowers to already attract pollinators at a time, when competition by other flower species is still low and visits by pollinators are often limited by low temperatures. Early flowering in turn allows seed set in late spring and early summer. The seeds have a fleshy structure attached, an elaiosome that contains lipids, sugars and vitamins. This makes them highly attractive to ants during a season when high‐quality foods are still in short supply and leads to dispersal of the seeds (myrmecochory). The elaiosome also contains a fatty acid that acts as an olfactory attractant. But what attracts ants, is also attractive for other seed predators such as mice. Long‐term survival of seeds (and thus germination) therefore greatly depends on the detachment of the elaiosome from the seed by the ants. There is much more than meets the eye with respect of stinking hellebore pollination and seed dispersal. It is an example of the highly complex interdependencies between plants, their blossoms, different animal species as well as yeasts and bacteria. [ABSTRACT FROM AUTHOR]

Summary: Why bread dough rises, although yeast cannot metabolize starch: Experiments with yeast Yeast is ideal for simple experiments to visualize metabolic processes, such as those known from baking bread, for example. Thus the metabolism of different sugars to carbon dioxide can be qualitatively demonstrated by inflating balloons or quantitatively by gas production in a fermentation tube (glass airlock for fermentation). The experiments presented can be used to answer the question of why yeast is added to bread dough even though it is not able to convert the starch present in the flour. [ABSTRACT FROM AUTHOR]

Newly series of Gemini surfactants have emerged which are composed of two hydrophobic tails and two cationic head groups linked by spacer group. Today, these cationic Gemini surfactants are attracting attention of the researchers as these surfactants are more efficient in lowering surface tension as the conventional ones. Cationic Gemini surfactants have lower critical micelle concentrations (CMC) and higher surface tension reduction as compared to those of corresponding monoalkyl ammonium salts. They have wide industrial and household applications. They can be used as emulsifiers, dispersing and anti-foaming agents etc. Cationic Gemini surfactants show good antimicrobial activity against gram-positive and gram-negative bacteria. Antimicrobial activity has also been studied against fungi and yeast species. These cationic Gemini surfactants can be used as antibacterial, antifungal, antiviral agents. This review paper deals with synthesis, antimicrobial activity, methods for determining antimicrobial activity (MIC means minimum inhibitory concentration) and applications of cationic Gemini surfactants. [ABSTRACT FROM AUTHOR]