The dark rounded bodies inside phloem cells are called sieve plates. They are not actually "bodies" but rather perforated cross-walls that separate adjacent phloem cells.

Here's a breakdown:

* Phloem: The vascular tissue in plants responsible for transporting sugars (produced during photosynthesis) from leaves to other parts of the plant.

* Sieve tubes: Long chains of specialized phloem cells, connected by sieve plates.

* Sieve plates: These plates have numerous pores that allow the flow of sugars and other nutrients through the sieve tubes.

* Dark appearance: The sieve plates appear dark because they are denser than the surrounding cytoplasm, and they contain a higher concentration of proteins.

Note: The dark rounded bodies are not "bodies" in the sense of organelles like mitochondria or chloroplasts. They are structural components of the cell walls that facilitate the flow of nutrients within the phloem.