Observe the relationship between the first two words and then fill in the fourth place.
fern : prothallus :: Moss : ……………

Explanation

To solve the analogy fern : prothallus :: moss : ?, we need to understand the relationship between the first two terms.

1. **Identify the relationship**: The first term is "fern," and the second term is "prothallus." In ferns, the prothallus is the gametophyte stage, which is a small, heart-shaped structure that produces gametes (sperm and eggs). This stage is crucial for the life cycle of ferns.

2. **Determine the corresponding term for moss**: Now, we need to find the equivalent term for "moss." Mosses belong to the group of plants known as bryophytes, which also have a gametophyte stage. In mosses, the dominant phase is also the gametophyte, and it produces structures that are involved in reproduction.

3. **Identify the reproductive structure in moss**: In mosses, the sporophyte (the diploid phase) develops a structure called the "spore capsule." This capsule is where the spores are produced and eventually released.

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