University:
Michigan State University
Course:
BS 162 | Organismal and Population Biology
Academic year:

2023
Views:

327

Pages:

2
Author:

drvnomyhv

Unicellular Microorganisms One-celled organisms, also called single-celled or unicellular organisms, must carry out all the functions that a multicellular organism needs to live, including eating, getting rid of waste, moving, etc. The most abundant onecelled organisms are bacteria. Bacteria are prokaryotic, so lack the nucleus and distinct organelles of eukaryotic organisms. One-celled, eukaryotic organisms include organisms from the Kingdom: Protista and include plantlike algae, animal-like protozoa, and fungi-like slime molds. In a drop of pond water, there can be many unicellular (and multicellular) organisms. In the illustration below, there are several different microorganisms. Amoeba are one-celled organisms that live in wet environments including ponds, wetlands, wet soil, and even human bodies. They have a movable shape and can extend pseudopods to reach for and engulf prey. They prey on smaller organisms, like bacteria. Paramecium are one-celled organisms that are covered in hair-like cilia that beat to propel them in a spirals through their aquatic environments. They feed on bacteria and other small protozoans. Euglena are one-celled protozoans with a whip-like flagellum that they use to propel themselves through their aquatic environment. Some euglena species have chlorophyll, so can produce their own food through photosynthesis. Euglena Amoeba Paramecium Classification of Unicellular Organisms Domains: Archaea, Eubacteria, Eukaryota Extreme Organisms unicellular, prokaryotic microorganisms unicellular and multicelled eukaryotic organisms Bacteria single-celled prokaryotic microorganisms Kingdoms: Protista, Fungi, Diverse group of unicellular organisms, including: • plant-like algae • animal-like protozoans • fungi-like slime molds Plantae, Animalia