Unit 265 Causes and spread of infection. Outcome 1 Understand the causes of infection Identify the differences between bacteria, viruses, fungi and parasites. Bacteria are a living organism that is found almost everywhere, in soil, water and even in the human body. Not all bacteria are harmful, and some bacteria that live in your body are helpful. For instance, Lactobacillus acidophilus — a harmless bacterium that resides in your intestines — helps you digest food, destroys some disease-causing organisms and provides nutrients.
Many bacterial infections can be treated with antibiotics although some strains are now becoming resistant. We are also able to immunise against a wide range of bacterial diseases. A virus is a smaller micro-organism that needs a hosts living cell to reproduce. It is very difficult to kill a virus and antibiotics do not work of viral infections. Some of the world’s most serious and deadly diseases are viral.
Others exist in the environment as spores of moulds A parasite is an organism that lives on or in another organism, harming the host. 1.2 Identify common illnesses and infections caused by bacteria, viruses, fungi and parasites Bacteria Tuberculosis Urinary tract infections Viruses Influenza Herpes Chickenpox and shingles Fungi Ringworm Candida Parasites Malaria Tapeworms 1.3 Describe what is meant by ‘infection’ and ‘colonisation’ sometimes we can have a disease causing organism living on/in us but not be showing symptoms of illness this is known as colonisation. If the organism is making us ill this is infection. 1.4 Explain what is meant by ‘systemic infection’ and ‘localised infection’ A systemic infection is in the bloodstream and has spread or is spreading around the body. They normally spread through the bloodstream and most of the infectious diseases known to the general public are examples of systemic infections (AIDs, flu, tuberculosis) Localised infections remain in one part of the body and do not cause problems
They are also found in radioactive waste, soil, plants, water ect.Some bacteria are completely harmless and help with our digestive system. The only place that bacteria aren’t found are where humans have sterilized. Some bacteria can cause diseases if they end up in the wrong part of our body. 1,1 Viruses are too small to be seen by the naked eye. They are even smaller then bacteria.
1.1 Identify the differences between bacteria, viruses, fungi and parasites Bacteria - a single cell micro-organism that gets its nutrition from its surroundings and can only be seen under a microscope. Viruses - are disease producing agents far smaller than bacteria. They are enclosed in a protein coating which makes them more difficult to destroy. Fungi – are included in the plant kingdom but are quite different from green plants. The basic unit of a fungus is a hypha which is a hollow tube.
A virus is a small infectious agent and can replicate only inside the living cells of an organism. Viruses can infect all types of organisms, from Animals, Humans Plants and even Bacteria by touch or air borne. Fungus or singular Fungi. Most fungi are inconspicuous because of the small size of their structures, and their lifestyles in soil, on dead matter, and after a long term relationship with plants, animals, or other fungi only becoming visible when reproducing. They also feed on many Bacteria in decaying matter organisms to survive.
CU254 : Causes and Spread of Infection 1. Understand The Causes Of Infection 1.1 Understand the differences between: Bacteria - Bacteria are a single cell group usually in many millions that can multiply rapidly. Viruses - A virus is infectious and replicates itself within living cells. Fungi - Fungi is a multi celled micro organism found in moulds and yeasts, it is a vital component in de-composition. Parasites - A parasite is an organism that lives on or within another living organism, it feeds off of the host.
Bacteria usually reproduce via binary fission, a form of asexual reproduction where the bacteria replicates its DNA then divides itself into two identical cells. Unlike viruses, bacteria do not need a host cell (although they still need nutrients) to reproduce. Harmful bacteria are referred to as pathogens. These pathogens cause disease that usually start in a specific location but when left untreated, can cause septiceamia (the blood becomes infected and unusable by the body) which leads to shock and ultimately death. Most bacterial infections produce pus, a substance containing dead white blood cells.
Disease Yersinia pestis The Plague Jesus Urquijo Biology 113 Lab March 18, 2013 Microbes are what make the world what it is today. They are found in nearly every environment on earth. Each species has its own way of getting nutrients and adapting to its environment, such as pH, aerobic and anaerobic conditions, and enzymes that are essential for optimum living. The majority of bacteria living on earth are harmless if not beneficial to the human race, but those few microbes that are harmful to humans are those that cause disease. They are referred to as pathogens and need to be observed so we can prevent the spreading of disease caused by those particular microbes.
Parasites are larger than bacteria, their cells contain a nucleus and share features with human cells. Some parasites replicate in the environment and some can only replicate within a host organism. Fungi are diverse in their shape and size, their cells have a nucleus and complex internal structures, they are found as environmentally resistant spores and molds and can cause disease in the form of yeasts. 2. Common illnesses and infections caused by bacteria, viruses, fungi And parasites: Bacteria Tuberculosis, pneumonia, tetanus, typhoid fever, diphtheria, salmonella.