ABSTRACT
Nutrition can affect these functions, so it is the purpose of this chapter to describe the functions of cells and their integration into the tissues, organs, and systems that function in the cycle of life. Like the cell with its cycle of formation, maintenance, and death, whole bodies have a life cycle that includes the stage from conception to birth, from birth to growth and development, to adulthood, and then to senescence. Scientists have learned much from these shorter-lived species about the processes involved and how nutrition can affect the time frame for these stages of the life cycle. Although much of what we have learned about nutrition has been gathered from human studies, there are limitations in what can be done with this species. The nutrition screening of people over the age of 65 can present some special problems and hurdles. In the human, these stages include: conception to birth, infanthood, childhood, adolescence, adulthood, and senescence.
