Final answer:
Cells with abundant smooth endoplasmic reticulum are typically those involved in producing steroid hormones, detoxifying compounds, and storing calcium ions, such as Leydig cells and liver cells.
Step-by-step explanation:
Cells that are likely to have a lot of smooth endoplasmic reticulum (SER) include those involved in the synthesis of lipids, metabolism of carbohydrates, detoxification of medications and poisons, and storage of calcium ions. Specifically, cells that make large amounts of steroid hormones, such as Leydig cells in the testes and cells in the ovaries, have abundant smooth ER. Other cell types with significant amounts of smooth ER are liver cells, which play a role in detoxifying compounds, and muscle cells, where a specialized form of smooth ER called sarcoplasmic reticulum stores calcium ions necessary for muscle contraction. Therefore, the correct answer to which cell type most likely has the greatest concentration of smooth ER is a cell that makes steroid hormones.