Si oze Viruses vary considerably in size. Although most are quite a bit smaller than bacteria, some of the larger viruses(such as the smallpox virus) are about the same size as some very small bacteria(such as the mycoplasmas, rickettsia, and chlamydia) Viruses range from 20 to 300 nm in diameter
Viruses vary considerably in size. Although most are quite a bit smaller than bacteria, some of the larger viruses (such as the smallpox virus) are about the same size as some very small bacteria (such as the mycoplasmas, rickettsias, and chlamydias). Size Viruses range from 20 to 300 nm in diameter
The comparative sizes of several viruses and bacteria: 225mm Bacterashase M13 IcOrm in diamter e 2 nm Totacroesaic vius Racte Cameta (a bacterin ●3m L5I nn x 2mnm poliovirus Vaccinia virus 3at nm x 20 nm x Ico nm Lanterns ch rm tnick ia iterum
The comparative sizes of several viruses and bacteria:
Genome in virion RNA RNA一DN VIruses viruses Viruses SS DNA ds dNA SS RNA ds RNA SS RNA ds RNA (Retroviruses) Hepadnaviruses) Viral genomes. The genomes of viruses can be composed of either DNa or rna, and some use both as their genomic material at different stages in their life cycle However, only one type of nucleic acid is found in the virion of any particular type of virus. This can be single stranded(ss), double-stranded(ds), or in the case of the hepadnaviruses, partially double-stranded
Genome in virion Viral genomes. The genomes of viruses can be composed of either DNA or RNA, and some use both as their genomic material at different stages in their life cycle. However , only one type of nucleic acid is found in the virion of any particular type of virus. This can be singlestranded (ss), double-stranded (ds), or in the case of the hepadnaviruses, partially double-stranded
6.2 Structure of viruses Most viruses are too small to be seen under light microscope. All viruses consists of an RNA or DNA core genome surrounded by a protein coat capsid. The combined viral genome and capsid is called the nucleocapsid capsid Envelope Capsomere Capsid Capsid capsomeres) Naked virus
• Most viruses are too small to be seen under light microscope. • All viruses consists of an RNA or DNA core genome surrounded by a protein coat capsid. • The combined viral genome and capsid is called the nucleocapsid. 6.2 Structure of viruses
The nucleic acid of a virus is surrounded by a protein coat called the capsid Each capsid is composed of protein subunits called capsomeres In some viruses, the capsid is covered by an envelope which usually consists of some combination of lipids proteins, and carbohydrates Depending on the virus envelopes may or may not be covered by spikes, which are carbohydrateprotein complexes that project from the surface of the envelope
The nucleic acid of a virus is surrounded by a protein coat called the capsid Each capsid is composed of protein subunits called capsomeres. In some viruses, the capsid is covered by an envelope, which usually consists of some combination of lipids, proteins, and carbohydrates. Depending on the virus, envelopes may or may not be covered by spikes, which are carbohydrateprotein complexes that project from the surface of the envelope