Monerans

   Monerans are one-celled  organisms that have no nucleus or organelles.  They do contain hereditary material but it is not contained in a nucleus.  Even with out these parts  moneran cells have the same same basic life processes as an animal cell. They reproduce, grow, and break down food to provide energy.  Molecules inside the cell carry out these process instead of organelles. 

    Unlike the cells that make up your body, monerans do not have one specific job.  for example the cells inside your brain have one job and the cells of your skin have another.  Monerans are individual cells that survive on their own.  They do not work together in groups.  However, they can be found in pairs, clumps, or in chains.   

   The Kingdom Monera is divided into two types or organisms,  bacteria and cyanobacteria.  Bacteria are monerans that consume food.  Thousands of these cells live on almost all of the surfaces we touch everyday.  They even live on our bodies.  All monerans have a cell wall, and most bacteria have a sticky capsule as an outer layer.  The capsule helps the cell stick to a food source or other cells.  It also helps keep the cell from drying out.  With a capsule the bacteria can survive in a variety of environments.  Bacteria still need certain conditions to survive.  They must have food, certain temperatures, and moisture.  The temperature can vary between freezing to near the boiling point.

   Bacteria undergo the process of respiration.  Respiration can be aerobic respiration, which is when the cell uses oxygen to help breakdown food into water and carbon dioxide, or it can be anaerobic, which is  respiration with out the use of oxygen.  Some bacteria can form what is called an endospore.  An endospore is a thick-walled structure that forms around the hereditary material and has a small amount of cytoplasm.  The rest of the cell may die but the endospore can live on for long periods waiting for the conditions to become favorable again.

   Under favorable conditions a bacteria cell may reproduce through fission.  Fission is when the cell duplicates the hereditary material then splits into two new cells each with a copy of the hereditary material.  Under the right circumstances bacteria can go through fission every twenty minutes.  Bacteria are important to us in many ways.  Most of them are consumers, which means that they need to consume food for energy.  Bacteria make up many of the organisms that help dead things decompose.  They get their food by breaking down dead things into smaller particles.  This returns minerals and other materials to the soil.  Some bacteria even live in your intestines and help you to digest your food while producing Vitamin K.  They also use bacteria in sewage treatment plants to help clean the water and make it reusable.

    Bacteria come in three main shapes: round called cocci, spiral called spirilla, and and rod shaped called bacilli.

   One problem with bacteria is that when some of them break down their food they produce a toxic chemical that can cause diseases.  These diseases are contagious, or can be passed from person to person.  The human body is a perfect place for bacteria to grow because it is warm, moist, and has a lot of food sources.  Some of the diseases caused by bacteria are: strep throat, blood poisoning, whooping cough, diphtheria, and tuberculosis.  With out medications it may be hard to rid your body of these bacteria.  Bacteria can also be harmful to plants. 

   Cyanobacteria are monerans that make their own food through the process of photosynthesis.  These cells are found in oceans, lake, pond, swimming pools, moist soil, and even leaky faucets.  These organisms are an important food source for many of the animals in the water.  They also use the oxygen given off during photosynthesis.  They reproduce through fission and some have sticky capsules like bacteria.  They can be found alone, in colonies, or long, thread like chains.  They can be harmful if they multiply too quickly and cover a pond or lake.  This would lead to the death of many organisms in the pond and cause the water to become unclean.  In the vast ocean these large groups don't cause problems. The large mounds of cyanobacteria in the ocean are called stromatolites .    These mounds can so old that the bottom layers are made up of fossilized cyanobacteria and the living ones grow on top.  They produce their food through photosynthesis.

   Louis Pasteur, a French scientist, found that bacteria caused many diseases.  He came up with many methods of keeping food from spoiling.  Pasteurization, named after Louis, is the process of heating food to a high temperature and then quickly cooled to kill the bacteria.  This process is used a lot with milk.  We can also protect ourselves from harmful bacteria by putting foods in the fridge, freezing them, covering them with something, and by cooking and washing at high temperatures.

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