Image: typical flower stained with safranin / Alzian blue.
Sepals: they are modified leaves protecting the inner flower structures.
Petals: they are modified leaves near the reproductive structures, stamen and pistil. The petal function is attracting pollinators and protecting the reproductive structures.
Style: it is the longer structure of the pistil that connects the ovary with the stigma. The pollen tube grows along the style to reach the ovary for fertilization.
Anther: it is the capsule of the stamen made up of two thecas, bags where pollen is found.
Theca: it is the bag that encloses the pollen. The theca is found in the anther of the stamen.
Pollen: it is the male gametophyte, which contains the microspore. Fertilization takes place when microspore and macrospore (in the female gametophyte of the ovary) are fused together.