Overall, life expectancy fell by one-tenth of a year, from 78.9 in 2014 to 78.8 in 2015, according to the latest data. The last time U.S. life expectancy at birth declined was in 1993, when it dropped from 75.6 to 75.4, according to World Bank data. The overall death rate rose 1.2 percent in 2015, its first uptick since 1999. More than 2.7 million people died, about 45 percent of them from heart disease or cancer.
The process by which new cells are made is called cell division. Cell division is occurring all the time. Around two trillion cell divisions occur in the average human body every day! Types of Cell Division. There are three main types of cell division: binary fission, mitosis, and meiosis.
The duration of time spent in interphase and in each stage of interphase is variable and depends on both the type of cell and the species of organism it belongs to. Most cells of adult mammals spend about 20 hours in interphase; this accounts for about 90% of the total time involved in cell division.Interphase includes G1, S, and G2 phases. Mitosis and cytokinesis, however, are separate from interphase. G2 (Gap 2), in which the cell resumes its growth in preparation for division. 2  In addition, some cells that do not divide often or ever, enter a stage called G0 (Gap zero), which is either a stage separate from interphase or an extended G1.