Matrotrophy associated with vertebrates and especially mammals, matrotrophy is found in 21 of 34 animal phyla, and is fairly common in 11 of those. It has arisen independently in more than 150 clades within Chordata and in more than 140 clades amongst invertebrates. Matrotrophy Matrotrophy is a form of maternal care during embryo development. Some flowering plants supplied the developing embryos for the first stages. The ovule has no stocks and the nutrients are provided by the "mother". In plants, matrotrophy is considered a critical evolutionary development preceding the origin of embryophytes and therefore essential to the evolution of land plants.
Subgroups of cyclic groups by "e" if and only if "e" is a divisor of "d". Divisibility lattices are distributive lattices, and therefore so are the lattices of subgroups of cyclic groups. This provides another alternative characterization of the finite cyclic groups: they are exactly the finite groups whose lattices of subgroups are distributive. More generally, a finitely generated group is cyclic if and only if its lattice of subgroups is distributive and an arbitrary group is locally cyclic if and only its lattice of subgroups is distributive. The additive group of the rational numbers provides an example of a group that is locally