What Is a Microorganism? Introduction to Microorganisms
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National Park Service U.S. Department of the Interior Zion National Park What is a Microorganism? Introduction to Microorganisms NPS/MARC NEIDIG Contents Introduction 2 Background 2 Activities How Small is Small? 3 Mystery Microorganisms 4 Microorganisms Are Everywhere – Even in Zion National Park! 6 Glossary 8 References 8 Introduction This guide contains background information about what microorganisms are and directions for three activities that will help students better understand microorganisms and how they relate to everyday life and Zion National Park. The activities are most beneficial to students when completed in order. This guide is specifically designed for sixth grade classrooms, but the activities can be modified for students at other levels. Theme A microorganism is defined as a living thing Though they cannot be seen with the that is so small it must be viewed with a naked eye, there are millions of diverse microscope. Some microorganisms like viruses microorganisms living everywhere around us, are so small they can only be seen with special performing a variety of important functions. electron microscopes. Focus There are five different categories of This activity guide provides the definition, and microorganisms—bacteria, algae, protozoa, explores examples of microorganisms, and the fungi, and viruses—explained in further detail places microorganisms are found. in Mystery Microorganisms. Microorganisms cover almost all the kingdoms of life. Bacteria Activities and some algae are in the Monera kingdom (sometimes divided into the separate How Small is Small? Eubacteria and Archaebacteria kingdoms), By using a large scale, students will be able algae and protozoa are in the Protista model the size of specific microorganisms and kingdom, and fungi make up their own compare them with the size of a human hair. kingdom. There is ongoing debate about how Activity Materials to classify most microorganisms (for instance, Corresponding materials Mystery Microorganisms some scientists put some types of algae in the which may include images, Students will learn about the five categories of Plant kingdom while others do not). worksheets, and answer keys are available for each activity. microorganisms by classifying a set of species Microorganisms of all kinds can be found in Materials can be downloaded (their “Mystery Microorganisms”). from the lesson plan webpage, Zion National Park and southern Utah. In found here. many cases, these microorganisms can actually Microorganisms Are Everywhere – be seen at work, such as the fungi, algae, and Even in Zion National Park! bacteria that build up the fragile spires of Core Connections Students will use a description and photo biological soil crust, or the algae which gives to categorize a species of microorganism Utah Core Curriculum the Emerald Pools a green color. Sixth Grade Science and determine where it might live in Zion National Park. Microorganisms are also prevalent inside us. Standard 5: Students will understand that While we like to think of ourselves as being microorganisms range from Background made up of human cells, we are actually simple to complex, are found 90% microbial: there are 10 times more cells almost everywhere, and are from microorganisms in our bodies than both helpful and harmful. Just as there are millions of different species of plants and animals in the world, human cells. That means there are trillions Objective 1: Observe and there are millions of different species of of microorganisms living inside us every day. summarize information about microorganisms. Microorganisms can survive Most are helpful to us, such as bacteria that microorganisms. in environments where humans are unable help us digest our food. Scientists now think that a diversity of microorganisms inside of us Objective 3: Identify positive to live. Microorganisms exist throughout the and negative effects of world, from Antarctica to your kitchen, from help us resist many diseases. microorganisms and how inside animals, like humans, to the expansive science has developed positive uses for some microorganisms wilderness in Zion National Park. and overcome the negative effects of others. Zion National Park, April 2014 What is a Microorganism? 2 How Small is Small? 2. Have students examine a human hair (one can be passed around and/or students can Duration examine their own). Students can look 45 Minutes at how thin the hair is with and without magnifying glasses. Location Outside or inside area with a large open space 3. Go outside or into your open space, and use the meter stick to measure an area 1 Key Vocabulary meter long. Mark it with chalk, string, or tape (depending on your location). One NIH organism, microorganism, single-celled, algae, bacteria, fungi, protozoa, virus meter represents the 0.1 millimeter width of a hair using the scale of 10,000 :1. Objectives Students will be able to conceptualize the size 4. Using the information below, add different of microorganisms and give a definition of microorganisms to the ground or paper. what a microorganism is. Students can measure out the size and label the different cells and microorganisms: Method By using a large scale, students will be able Human red blood cell (.01 mm) = 10 cm model the size of specific microorganisms and Paramecium (protozoa) (0.2 mm) = 2 m PROYECTO AGUA compare them with the size of a human hair. The rod shape of E. coli can be Euglenoids (algae) (0.4 mm) = 4 m clearly seen under a scanning electron microscope. Background Scenedesmus (algae) (0.03 mm) = 30 cm Micrasterias americana algae at The average human hair is 0.1 millimeters E. coli bacteria (.002 mm) = 2 cm 400x magnification. wide, and barely discernable with the naked Staphylococcus bacteria eye. Microorganisms are many hundreds to (.0005 mm) = 0.5 cm thousands of times smaller and by definition can only be seen under a microscope. Polio virus (.00002) = .2 mm (a tiny dot) Most microorganisms consists of only one cell and they are known as single-celled 5. When finished measuring out all the organisms (in comparison, humans consist microorganisms, compare their sizes. of trillions of different cells). Different Notice how viruses are the smallest type species of microorganisms vary in size, shape, but other types vary in size depending on appearance, and way of surviving. the species. Students can draw their own reference models on paper to keep. The largest microorganisms are most fungi and many species of protozoa. Viruses are 6. Finish by asking students (verbally or in by far the smallest of all microorganisms. If writing) why scientists have to use models a virus was the size of a baseball, an average like this (because some microorganisms bacterium would be the size of a pitcher’s are too small to be seen under regular mound, and one single human cell would be microscopes and it is difficult to the size of the entire stadium! compare sizes and features of a variety of microorganisms because of their size). Materials • meter stick or ruler Extension • magnifying glass Have students research the size of other • marking material for ground (i.e. sidewalk microorganisms to compare size and practice chalk, markers, or string) math skills using the 10,000:1 scale. • a hair from a human head • 5 meters of butcher paper (if inside) Find large items to compare microorganisms to such as a pencil, a school bus, or a football Suggested Procedure field. For instance, if the 2,000 foot tall cliffs of 1. Introduce the idea of what microorganisms Zion Canyon were on the scale, they would be are and that they cannot be seen with the over 3,800 miles long, the distance from Las naked eye. Vegas to Chicago and back! Zion National Park, April 2014 What is a Microorganism? 3 Mystery they reproduce using spores, tiny, seed-like cells. Most fungi are multicellular, but others Microorganisms such as yeast are single-celled. Most cells of fungi are loosely connected through thread- Duration like filaments called hyphae. Fungi is plural, 45 Minutes fungus is singular. Location Protozoa: The name protozoa means “first Inside animal,” and describes this microorganism’s ability to move and hunt. Protozoa are ROBIN S Key Vocabulary members of the Protista kingdom. Ciliates, organism, microorganism, single-celled, algae, amoebae, and flagellates all are categories bacteria, fungi, protozoa, virus, producer, of protozoa and all are single-celled. Most decomposer protozoa do not cause disease but there are a few that cause harm to humans, including Objectives Plasmodium (malaria) and Giardia. These Students will be able to list the five different protozoa are considered parasites. Protozoa is types of microorganisms and share the specific plural, protozoan is singular. attributes of at least one type. Viruses: There is some debate on whether HHS Method viruses are actually organisms at all; that is, Students will learn about the five categories of whether they are alive or not. While they microorganisms by classifying a set of species have DNA or RNA and infect a host like (their “Mystery Microorganisms”) as one of other parasites, viruses have no true cells and the types of microorganisms. cannot reproduce on their own. Viruses is plural, virus is singular. Background Generally, there are five categories of Materials microorganisms (simpler definitions are • Mystery Microorganism Clues sheets located in the glossary for student use): • Large (8.5 x 11) envelopes NPS/BRYANNA PLOG Digital interpretation of Bacteria: These microorganisms are the Suggested Procedure rhinovirus. oldest living things on Earth, and have been 1. Prepare “mystery packets” ahead of time Aspergillus fumigatusas, a fungi, around an estimated 3 billion years (scientists visible under a microscope. using the Mystery Microorganism Clues have found fossils of cyanobacteria). They sheets. Print one set of each and put them Algae color the water green at come in a variety of shapes (spheres, rods, the Emerald Pools.