What is the name of the chamber that produces and holds spores in ferns?

The chamber that produces and holds spores in ferns is indeed called a sporangium. This structure is crucial in the life cycle of ferns, as it is within the sporangium that meiosis occurs, resulting in the formation of haploid spores. Once mature, the spores are released from the sporangium, facilitating the dispersal and continuation of the fern's reproductive cycle.

While the other terms relate to various aspects of ferns, they serve different functions. A sorus is a cluster of sporangia, typically located on the underside of a frond, but it is not the chamber itself where the spores are produced and held. The prothallium refers to the gametophyte stage of the fern, which develops from the spore after germination, allowing for fertilization to occur. A frond is the leaf-like structure of the fern, which may bear the sori but does not directly produce or hold the spores itself. Understanding each term and its role is essential in grasping fern biology and their reproductive strategies.