Today, the Railroad Retirement program is closely tied to the far better-known Social Security program, and although the Railroad Retirement program and Social Security share a number of common elements, key differences also exist between the two in areas such as funding and benefit structure.
The Cell Cycle. The cell cycle is the life cycle of a cell (Figure 5.3). At the end of the cell cycle, after mitosis has taken place, the parent cell no longer exists; it has given rise to two daughter cells. There are two phases in the cell cycle, interphase and mitosis.
The term cellular respiration refers to the biochemical pathway by which cells release energy from the chemical bonds of food molecules and provide that energy for the essential processes of life. All living cells must carry out cellular respiration. It can be aerobic respiration in the presence of oxygen or anaerobic respiration. Prokaryotic cells carry out cellular respiration within the cytoplasm or on the inner surfaces of the cells. More emphasis here will be placed on eukaryotic cells where the mitochondria are the site of most of the reactions.