At one time, fungi were included in the plant kingdom. Although fungi look like plants, they are more closely related to animals than they are to plants. What is one characteristic of fungi that clearly separates them from all plants? Question 13 options: Fungi are sessile. Some fungi can reproduce by producing spores. Fungi are heterotrophic, eukaryotic organisms. Some fungi develop a mycelium. Fungal cells have cell walls.

To determine which characteristic clearly separates fungi from all plants, let's analyze each option:

1. Fungi are sessile.

   • Being sessile means that an organism does not move and is fixed in one place. Both fungi and plants are sessile, so this characteristic does not separate fungi from plants.

2. Some fungi can reproduce by producing spores.

   • Many plants, such as ferns and mosses, also reproduce by producing spores. Therefore, this characteristic is not unique to fungi.

3. Fungi are heterotrophic, eukaryotic organisms.

   • This is a key characteristic. Fungi are heterotrophic, meaning they obtain their food by absorbing nutrients from other organisms. In contrast, plants are autotrophic, meaning they produce their own food through photosynthesis. This characteristic clearly separates fungi from plants.

4. Some fungi develop a mycelium.

   • While the development of a mycelium (a network of fungal threads or hyphae) is specific to fungi, it is not a characteristic that separates all fungi from all plants, as it is not a universal feature of all fungi.

5. Fungal cells have cell walls.

   • Both fungi and plants have cell walls, although the composition is different (fungal cell walls contain chitin, while plant cell walls contain cellulose). This characteristic does not clearly separate fungi from plants.

Based on the analysis, the characteristic that clearly separates fungi from all plants is:

Fungi are heterotrophic, eukaryotic organisms.