Cell wall for higher growth rates in diatoms. In brown algae, phlorotannins may be a constituent of the cell walls. The group Oomycetes, also known as water molds, are saprotrophic plant pathogens like fungi. Until recently they were widely believed to be fungi, but structural and molecular evidence has led to their reclassification as heterokonts, related to autotrophic brown algae and diatoms. Unlike fungi, oomycetes typically possess cell walls of cellulose and glucans rather than chitin, although some genera (such as "Achlya" and "Saprolegnia") do have chitin in their walls. The fraction of cellulose in the walls is no more than 4
Sexual selection in fungi by producing pheromones. In the isogamous budding yeast, Saccharomyces cerevisiae, pheromones are used to distinguish between different mating types and show a preference for higher concentrations of pheromones along with a rejection of lower concentrations. However, all of the pheromone studies within fungi have been performed in a laboratory. In order to further support this hypothesis, more research is necessary on the effects of natural gamete density, motility, and pheromone production in nature., Mushroom-forming fungi within Basidiomycetes produce sexually by the reciprocal migration of nuclei and have a male-biased OSR which aids in supporting that sexual selection is present within