Cells atop the stalk form an asexual fruiting body that contains haploid spores. As with plasmodial slime molds, the spores are disseminated and can germinate if they land in a moist environment. One representative genus of the cellular slime molds is Dictyostelium , which commonly exists in the damp soil of forests. There are over , described living species of protists. Nearly all protists exist in some type of aquatic environment, including freshwater and marine environments, damp soil, and even snow.
Paramecia are a common example of aquatic protists. Due to their abundance and ease of use as research organisms, they are often subjects of study in classrooms and laboratories. In addition to aquatic protists, several protist species are parasites that infect animals or plants and, therefore, live in their hosts. Amoebas can be human parasites and can cause dysentery while inhabiting the small intestine.
Other protist species live on dead organisms or their wastes and contribute to their decay. Approximately species of slime mold thrive on bacteria and fungi within rotting trees and other plants in forests around the world, contributing to the life cycle of these ecosystems. Learning Objectives Describe the habitats and life cycles of various protists. Key Points Slime molds are categorized on the basis of their life cycles into plasmodial or cellular types, both of which end their life cycle in the form of dispersed spores.
Plasmodial slime molds form a single-celled, multinucleate mass, whereas cellular slime molds form an aggregated mass of separate amoebas that are able to migrate as a unified whole. Slimes molds feed primarily on bacteria and fungi and contribute to the decomposition of dead plants. Key Terms haploid : of a cell having a single set of unpaired chromosomes sporangia : an enclosure in which spores are formed also called a fruiting body plasmodium : a mass of cytoplasm, containing many nuclei, created by the aggregation of amoeboid cells of slime molds during their vegetative phase diploid : of a cell, having a pair of each type of chromosome, one of the pair being derived from the ovum and the other from the spermatozoon.
Article Slime Molds. Fuligo septica, or "dog vomit" slime mold, is a common species of slime mold found in Mount Rainier National Park. Plasmodial slime mold threads on rotting wood.
Vecchio Photo On the other hand, plasmodial slime molds start out as individual amoeboid cells, but join together to form a multi-nucleate mass having only one cellular membrane a "super-cell" containing multiple nuclei. You Might Also Like. Loading results Tags: mount rainier slime mold biology protists science mount rainier science ecology. Related Articles Go! Related People Loading results Related Places Loading results Last updated: September 28, Fungus-like protists… Welcome to the fungus-like protists page.
Water Mold Another type of fungus-like protists is water mold. Most of them are small single-celled organisms. Some of them are decomposers But others are parasites Some parasitic water molds cause diseases These protists still endanger crops today.
Slime molds Thin masses of living matter.
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