Answer:
An angiosperm seed contains structures contributed by three generations of plants.
Step-by-step explanation:
The spermatophytes, also known as phanerogams, represent a group of seeded plants that have developed special structures for reproduction. This group (spermatophytes) consists of gymnosperms or 'naked seeds', and angiosperms or 'enclosed seeds'. The seed is an organ generated from the ovule after fertilization by the pollen grain, which gives rise to a seedling during the process of germination. In flowering plants, seeds are generated by a process of double fertilization and consist of three tissues: 1-an embryo (generally diploid) formed by repeated mitotic division of the zygote cell, 2- an endosperm tissue (generally triploid, 3n) that nourishes the embryo during its growth, and 3-a seed coat generated from the integuments of the ovule. In angiosperms, seeds consist of three generations: the gametophyte that provides nutrients to the embryo, the embryo, and the seed coat which is generated from the parental tissue (sporophyte).