Most centipedes need to live in moist places, but a few can survive in deserts and dry grasslands. 1  These animals are found in the following types of habitat. 2  temperate. 3  tropical. terrestrial.  Terrestrial 1  Biomes. taiga.  desert or 1  dune. chaparral. 2  forest. rainforest. 3  scrub forest.  mountains.
Yeast are among the few living organisms that do not need oxygen in order to produce energy. This oxygen-independent state is called anaerobic (pronounced a-na-ROE-bik; without oxygen). During such anaerobic conditions, yeast convert carbohydratesâstarches and sugarsâto alcohol and carbon dioxide gas. This process is known as fermentation. The fermentation process of yeast is caused by enzymes, catalysts in chemical reactions similar to the digestive enzymes in the human body.
Yeast is a leavening agent. Yeast releases CO2 as a waste product. Bread dough has protein structures called Gluten. The CO2 from the yeast gets trapped in pockets between the gluten strands, thus causing the dough to rise. When the bread bakes, the yeast continues to reproduce and create CO2 gas. The yeast eventually dies when the temperature of the dough gets hot enough. Without yeast, bread would be flat and tough.