Final answer:
Cells in the lateral meristem differentiate into vascular tissues such as xylem and phloem. Parenchyma is an example of a simple tissue. Cells with lignin-rich thick walls that are stained with a lignin-binding dye are likely part of the xylem.
Step-by-step explanation:
When scientists label cells in the lateral meristem of a sapling with a dye, they do so to track the development of those cells into different tissue types. Since lateral meristem is associated with growth in thickness, the tissues that are most likely to be stained by the dye are vascular tissues such as xylem and phloem, which are involved in the transport of water, minerals, and sugars throughout the plant. Therefore, out of the options given—dermal tissue, xylem, phloem, and ground tissue—the correct answers would be (b) xylem and (c) phloem.
Simple tissues in plants are composed of one type of cell. Therefore, the sample that would represent a simple tissue out of the given options would be the one with parenchyma cells, as they are a single cell type, making (c) parenchyma showing only one type of cell the correct answer.
If we are staining with a dye that binds lignin, the preferentially stained cells would be those with thick walls involved in support and water transport, which are characteristic of vascular tissues, specifically secondary xylem.