ABC model of flower development well as in the determination of the floral meristem. Therefore, the "AG" mutants are devoid of androecium and gynoecium and they have petals and sepals in their place. In addition, the growth in the centre of the flower is undifferentiated, therefore the petals and sepals grow in repetitive verticils. The "PLENA" ("PLE") gene is present in "A. majus", in place of the "AG" gene, although it is not an ortholog. However, the "FARINELLI" ("FAR") gene is an ortholog, which is specific to the development of the anthers and the maturation of pollen. In "Petunia", "Antirrhinum" and in maize the C
Flower female flowers on the same plant may not appear or mature at the same time, or pollen from the same plant may be incapable of fertilizing its ovules. The latter flower types, which have chemical barriers to their own pollen, are referred to as self-sterile or self-incompatible. Plants cannot move from one location to another, thus many flowers have evolved to attract animals to transfer pollen between individuals in dispersed populations. Flowers that are insect-pollinated are called "entomophilous"; literally "insect-loving" in Greek. They can be highly modified along with the pollinating insects by co-evolution. Flowers commonly have glands called "nectaries"