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BACTERIA
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BACTERIA
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MONERA The Monera are single-celled organisms that do not possess a true nucleus, they are presently divided into two large Kingdoms, the Eubacteria and Archeobacteria. They are divided into these groups dependant on their nuclear structure. Their nucleus has no outer membrane and the cell is called prokaryotic. All other living organisms are eukaryotic, which have a membrane surrounding the nucleus. Monera (sometimes referred to as bacteria or blue green algae) are microscopic. They are either autotrophic or heterotrophic. An autotroph is an organism that can build its own food from "chemicals" like carbon dioxide and water. Monera that do not make their own food are heterotrophic and must seek a supply of food. Heterotrophs depend on tissues, remains, and wastes of other living organisms for food. Bacteria come in 3 different shapes. Bacillus are rod shaped, coccus are spherical, and spirillum are spiral. Bacteria reproduce by asexual means, usually by dividing. Bacteria can be found just about everywhere, they are in air, water, inside you, outside you, in the frozen Arctic and even in hot springs. Some bacteria are responsible for food spoilage, and others are useful in changing food to a different desirable flavor or consistency such as in making cheeses. High temperatures kill most bacteria and this knowledge led to the discovery of pasteurization or the heating of milk to kill any bacteria that would lead to spoilage. Canning food or heating food and sealing it in air tight container also prevents spoilage. Cooling bacteria slows down their decomposing action and this led to the use of refrigeration and freezing to retard spoilage. Blue-green algae or cyanobacteria, unlike some bacteria, undergo photosynthesis. They carry on cell division and respiration. Some are harmful in that they may add to the pollution of lakes and rivers by their rapid growth, but most are benign. Cyanobacteria are one of the most primitive organisms found in the fossil record, making massive mounds 600 million years ago (stromatolites). MATERIALS: transmitted light microscope
BACKGROUND INFORMATION: Monera are single-celled organisms that do not possess a true nucleus. Their nucleus has no outer membrane and the cell is called prokaryotic. All other living organisms have a eukaryotic nucleus. Monera (or sometimes referred to as bacteria) are microscopic. They are either autotrophic or heterotrophic. An autotroph is an organism that can build its own food from "chemicals" like carbon dioxide and water. Monerans that do not make their own food are heterotrophic and must seek a supply of food. Heterotrophs depend on tissue, remains and wastes of other living things for food. There are two major groups that we will discuss during this lab: bacteria and blue green algae (cyanobacteria). Bacteria come in 3 different shapes. Bacillus are rod shaped bacteria, coccus are round shaped, and spirillum are spiral in shape. Bacteria reproduce by asexual means, usually by dividing. Bacteria can be found just about everywhere, they are in air, water, inside you, outside you, in the frozen Arctic and even in hot springs. Bacteria are responsible for food spoiling, as well as useful in changing food to a different desirable flavor or consistency such as in making cheeses. High temperatures kill most bacteria. This knowledge led to the discovery of pasteurization or heating milk to kill any bacteria that would lead to spoilage. Canning food or heating food and sealing it in airtight containers also prevents spoilage. Cooling bacteria slows down their decomposing action and this led to the use of refrigeration and freezing. Blue-green algae or cyanobacteria, unlike some bacteria, photosynthesize. They carry on cell division and respiration. Some are harmful in that they may add to the pollution of lakes and rivers by their rapid growth. Blue green algae are one of the most primitive organisms found in the fossil record, making massive mounds 600 million years ago (stromatolites).
PROCEDURE: In this activity the students will examine different examples of the Monera Kingdom. Monerans are not easy to see, but students should be able to use the transmitted light microscope to identify the different types. Using a light microscope and prepared slides, examine one example of each of the following: coccus, spirillum and bacillus. Using the living specimens look for blue-green algae. 1. Examine each slide using low power first, then high power.
BIOLOGICAL SCIENCES-MONERA PROBLEM: How can you distinguish the different types of Monera. HYPOTHESIS: ___________________________________________________________________ PROCEDURE: MATERIALS: microscope, prepared slides, live material 1. Examine each slide using low power first, then high power.
CONCLUSION: Describe the difference among them Monera. _____________________________________________________________________
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