Scanning electron micrograph (SEM) of yeast cells,Saccharomyces cerevisiae,commonly known as baker's yeast. Yeast is a kind of single celled fungus. It is able to ferment sugar,producing alcohol and carbon dioxide in the process. It has long been used in the brewing of beer,the production of wine and in the baking of leavened bread (carbon dioxide causes the dough to rise). Medically,dried yeast is used as a source of vitamin B1,riboflavin,and nicotinic acid. Yeast cells divide rapidly by budding off new cells (visible here). They can also reproduce sexually. Magnficiation: x370 at 35mm size. Gold tint. Original is BW B250/171. Reference: MICROCOSMOS,figure 5.37,page 107 |