The usage of molds and yeast in industry and sanitation. The potential threat of viruses Essay

Yeast is fungi which predominantly develop in the from of unicellular element. It is difficult to draw a distinct line between mold and yeast. Molds grow at low temperatures, while the presence of some nutrients, such as blood, glucose, compounds containing  SH group etc. and the absence of oxygen are favorable for the development of yeast like cells.

2.3.9.2. Economic Importance 

Molds and Yeast have a high enzymatic activity and are used in industry and sanitation. Some types of yeast grow to give valuable products, such as alcohol, acetones etc., while, other destroy organic matter of vegetable and animal remnants (leftovers). Molds are used to produce antibiotics.

2.3.10. Viruses

These are the smallest plants less than 0.3m in diameter. Viruses are obligate (essentially) intracellular parasites which can reproduce only within a specific host cell. They are all parasitic and lack normal metabolic functions, lying on the borderline between living organisms and chemical compounds. It is debatable whether viruses are living or nonliving. Viruses are unique in that they direct an infected cell to make virus parts and then assemble the parts into finished virus particles. Thus viruses are made in a cell and do not grow like bacteria which increases in size and then divide.

Viruses represent a primitive form of life  perhaps the first aggregation of fragments of nucleic acid and protein with any resemblance of life that gave rise to all higher forms of plants and animals.

All things considered Viruses should be considered as viruses because viruses are viruses. An infectious agent is considered to be a virus if it meets certain criteria.

2.3.10.1. Shape and size of viruses 

Viruses may have one of several basic symmetries such as

1.  Cubic  Polio virus, hapesviruses
2. Helical  TMV (rodshaped)
3. Complex  T phages, pox viruses

The viruses range in size from 0.01 to 0.3 microns.

2.3.10.2. Viral Diseases 

Many diseases e.g influenza, poliomyelitis, small pox, chickenpox infectious hepatitis, yellow fever etc. are caused by virus infections.

Enteric viruses  those viruses excreted in feces  are present in sewage and polluted waters. Due to their small size viruses are difficult to remove from water and they are resistant to normal disinfection methods as well.

2.4 Waterborne enteric diseases

Enteric It is related to small intestine. Obviously enteric diseases refer to the diseases caused through the ingestion of contaminated food or drink via mouth and/or direct contact with feces or vomit of an infected person or infected object. When the pathogen transmission medium is water then diseases caused are known as water borne enteric diseases. The potential for drinking water contamination is always present. The chances of outbreaks of enteric disease, bacteria, viral and amoebic through common water supply always looms large over the communities not being supplied adequately treated water. The incidence of waterborne disease is very low where community drinking is disinfected.

Some of the important diseases which are transmissible by the water  route are