Secondary succession occurs in areas lacking vegetation where soil is present.
Explanation:
Secondary succession always occurs in the place where there had been community living, but were destroyed.
These succession occurs in the place that lacks the vegetation.
For example: after the forest fire, the vegetation is destroyed but the soil is present. The succession in forest after massive forest fire is secondary succession.
If the place has never been colonized before then primary succession occurs.
The human skeleton performs six major functions: support, movement, protection, production of blood cells, storage of minerals, and endocrine regulation
