Effect Of Temperature On Respiration Of Yeast

Living organisms catabolize organic molecules within their cells and use the energy released to manufacture ATP by phosphorylating ADP. Many prokaryotes and virtually all Eukaryotes phosphorylate ADP either through fermentation (anaerobic) or respiration (aerobic). Both of these processes involve oxidation of foodstuffs, yet only the latter requires oxygen.

Cellular respiration is a very complex process that consists of many steps that take place inside the cell, in an organelle called a mitochondrion. Mitochondria are responsible for converting digested nutrients into the energy-yielding molecule adenosine triphosphate (ATP) to fuel the cell's activities. This function, known as aerobic respiration, is the reason mitochondria are frequently referred to as the powerhouse of the cell. There are two types of respiration that occur in cells to produce energy. When oxygen is available in the cell, aerobic respiration, as mentioned previously, occurs. When oxygen is not readily available, anaerobic respiration occurs.

Warmer temperatures hold less oxygen, thus triggering higher organism growth and respiration rates. We then took readings of the carbon dioxide level in each pipet every five minutes. Each of the pipets were placed in very different temperatures.

After a half an hour of being emerged in their respective temperatures, we found that the yeast in the incubator, after being in a very warm temperature of 50 degrees Celsius, had the most dramatic CO2 production of the three tested. Certain cells, like yeast cells produce ethyl alcohol through fermentation. Respiration in the presence of oxygen makes possible the complete oxidation of nutrient compounds into carbon dioxide and water. Using three glass pipets to hold the yeast mixture, we then sealed one end, and flipped the pipets upside down so to record the level of carbon dioxide that developed. In fact, ninety percent of the energy yield from the respiratory breakdown of nutrients

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