0 the series of changes that a living thing goes through from the beginning of its life until death -- 生命週期；生活週期，生活史
Proportions are general, depending on family size and stage in the life cycle.
However, in seeds of many species, dormancy is not an all or nothing stage in the plant's life cycle.
For example, depressive episodes in older adults with early-onset depression might represent a resurrection of unresolved issues from earlier tasks of the life cycle.
Independently of current residence and schooling, life cycle stage was strongly related to contraceptive usage.
This univoltine insect spends more than three-quarters of its life cycle in dormancy.
Nor is it the case that relevant contexts broaden over the entire life cycle.
A life cycle model is formulated within an optimization framework and solved by non-linear programming methods.
Individual preferences are represented by a logarithmic life cycle utility function.
