Virus is a microscopic particle that can infect the cells of a biological organism.
Viruses can only replicate themselves by infecting a host cell and therefore cannot reproduce on their own.
At the most basic level, viruses consist of genetic material contained within a protective protein coat called a capsid; the existence of both genetic material and protein distinguishes them from other virus-like particles such as prions and viroids.
They infect a wide variety of organisms: both eukaryotes (animals, fungi and plants) and prokaryotes (bacteria).
A virus that infects bacteria is known as a bacteriophage, often shortened to phage.
The study of viruses is known as virology, and those who study viruses are known as virologists.
It has been argued extensively whether viruses are living organisms.
Most virologists consider them non-living, as they do not meet all the criteria of the generally accepted definition of life.
They are similar to obligate intracellular parasites as they lack the means for self-reproduction outside a host cell, but unlike parasites, viruses are generally not considered to be true living organisms.
A primary reason is that viruses do not possess a cell membrane or metabolise on their own - characteristics of all living organisms.
Examples of common human diseases caused by viruses include the common cold, the flu, chickenpox and cold sores.
Serious diseases such as Ebola, AIDS, bird flu and SARS are all also caused by viruses. virus is a microscopic particle that can infect the cells of a biological organism.
Viruses can only replicate themselves by infecting a host cell and therefore cannot reproduce on their own.
At the most basic level, viruses consist of genetic material contained within a protective protein coat called a capsid; the existence of both genetic material and protein distinguishes them from other virus-like particles such as prions and viroids.
They infect a wide variety of organisms: both eukaryotes (animals, fungi and plants) and prokaryotes (bacteria).
A virus that infects bacteria is known as a bacteriophage, often shortened to phage.
The study of viruses is known as virology, and those who study viruses are known as virologists.
It has been argued extensively whether viruses are living organisms.
Most virologists consider them non-living, as they do not meet all the criteria of the generally accepted definition of life.
They are similar to obligate intracellular parasites as they lack the means for self-reproduction outside a host cell, but unlike parasites, viruses are generally not considered to be true living organisms.
A primary reason is that viruses do not possess a cell membrane or metabolise on their own - characteristics of all living organisms.
Examples of common human diseases caused by viruses include the common cold, the flu, chickenpox and cold sores.
Serious diseases such as Ebola, AIDS, bird flu and SARS are all also caused by viruse
Let's imagine two systems, one with 50 species and one with 4000. Both of them experience a draught and as a result 25 species of the first one die (that's quite likely) and 800 of the second population die out (more would not be very likely). So the first one lost 50% of species and the second one 20% - that means that the second one, with greater biodiversity has a bigger stability:)
because this fuel is generated by the breakdown of organic matter by anaerobic bacteria and is used in energy production . It is a renewable energy source produced biologically through anaerobic digestion. It occurs naturally in compost heaps, as swamp gas, and as a result of enteric fermentation in cattle and other ruminants. It is burned to generate heat or used in combustion engines to produce electricity.
