Bacteria
Bacteria1 are unicellular microorganisms, a few micrometres long, of various shapes such as spheres and spirals. The celi structure iis simpler than that of other organisms as there is no nucleus. Their control centre with genetic information is in a single loop of DNA. Some bacteria have an extra circle of genetic materiai called a plasmid which contains genes that give the bacterium some advantage over other bacteria like resistance to certain antibiotics.
Some varieties live in extreme cold or heat, while others live in people's intestines, where they help digest food. Most bacteria cause no harm to people.
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What are the 5 most common shapes of a bacterium? Choose from the following:
arrow ·comma· corkscrew • cylinder • linear • rod • spherical • spirai
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1 Are bacteria and germs the same thing?
Viruses
Viruses are microscopie organisms that exist almost everywhere on Earth. They are smaller than bacteria and require living host , people, animals or plants, to multiply. For this reason, they are classified as parasitic. They infect the cells of biological organisms and take over the cell mechanism redirecting it to produce the virus. They consist of genetic material, RNA and DNA, surrounded by a coat of protein, lipid or glycoprotein.
The most important distinction between bacteria and viruses is that antibiotics usually kill bacteria, but they are ineffective against viruses. Sometimes it is difficult to determine if a symptom is caused by a virus or a bacterium and the inappropriate use of antibiotics leads to the creation of bacterial diseases that are resistant to treatment.
Fungi
Fungi1 are of great environmental and medicai importance. Some live freely in water and in the soil, while others form parasitic or symbiotic relationships with plants and animals.
Mycosis is a common fungal infection which develops thanks to a variety
of environmental and physiological conditions. Inhalation of fungal spores or localised colonisation of the skin may initiate an infection; therefore mycoses often start in the lungs or in the skin.
Fungal infection of the skin is a widespread disease affecting people all over the world.
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1 Mushrooms are fungi, and are usually placed in a kingdom of their own apart from plants and animals.
