V. Short Answer Questions
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What are microorganisms? Name the five major groups of microorganisms.
How do we know when food becomes unfit for consumption due to microbial action?
How do diseases spread through insects? What are the insects that carry pathogens called?
How do viruses increase their numbers?
Give examples of natural and chemical preservatives. List the food items in which they are used.
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Answers
Answer:
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A microorganism, or microbe, is a microscopic organism, which may exist in its single-celled form or a colony of cells.
Microorganisms are divided into seven types: bacteria, archaea, protozoa, algae, fungi, viruses, and multicellular animal parasites ( helminths ). Each type has a characteristic cellular composition, morphology, mean of locomotion, and reproduction
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Invertebrates spread bacterial, viral and protozoan pathogens by two main mechanisms. Either via their bite, as in the case of malaria spread by mosquitoes, or via their faeces, as in the case of Chagas' Disease spread by Triatoma bugs or epidemic typhus spread by human body lice.
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Insects (mosquitoes, lice, fleas, bed bugs) and ticks are able to transmit a number of diseases caused by infectious agents: viruses (chikungunya virus, yellow fever, dengue fever, etc.), bacteria (Lyme disease, plague, etc.), parasites (malaria, sleeping sickness, leishmaniasis, filariasis, etc.)
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The dynamics of viral infections have been studied extensively in a variety of settings, both experimentally and with mathematical models. The majority of mathematical models assumes that only one virus can infect a given cell at a time. It is, however, clear that especially in the context of high viral load, cells can become infected with multiple copies of a virus, a process called coinfection. This has been best demonstrated experimentally for human immunodeficiency virus (HIV), although it is thought to be equally relevant for a number of other viral infections. In a previously explored mathematical model, the viral output from an infected cell does not depend on the number of viruses that reside in the cell, i.e. viral replication is limited by cellular rather than viral factors. In this case, basic virus dynamics properties are not altered by coinfection.
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Chemical food preservatives
Benzoates (such as sodium benzoate, benzoic acid)
Nitrites (such as sodium nitrite)
Sulphites (such as sulphur dioxide)
Sorbates (such as sodium sorbate, potassium sorbate.
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Contents
Basic foods
Legumes
Edible plants
Edible fungi
Edible nuts and seeds
Baked goods
Breads
Dairy products
Eggs
Meat
Cereals
Rice
Other
Seafood
Staple foods
Prepared foods
Appetizers
Condiments
Confectionery
Convenience foods
Desserts
Dried foods
Dumplings
Fast food
Fermented foods
Halal food
Kosher food
Noodles
Pies
Salads
Sandwiches
Sauces
Stews
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