Viruses are tinier: the largest of them are smaller than the smallest bacteria. All they have is a protein coat and a core of genetic material, either RNA or DNA . Unlike bacteria, viruses can’t survive without a host. They can only reproduce by attaching themselves to cells.
What is the basic structure of bacteria?
Structure. Bacteria (singular: bacterium) are classified as prokaryotes, which are single-celled organisms with a simple internal structure that lacks a nucleus, and contains DNA that either floats freely in a twisted, thread-like mass called the nucleoid , or in separate, circular pieces called plasmids.
What is the structure of bacteria and viruses?
Viruses are tinier: the largest of them are smaller than the smallest bacteria. All they have is a protein coat and a core of genetic material, either RNA or DNA . Unlike bacteria, viruses can’t survive without a host. They can only reproduce by attaching themselves to cells.
What is the basic structure of a virus?
The simplest virions consist of two basic components: nucleic acid (single- or double-stranded RNA or DNA) and a protein coat , the capsid, which functions as a shell to protect the viral genome from nucleases and which during infection attaches the virion to specific receptors exposed on the prospective host cell.
What special structures do bacteria and viruses have?
In addition to the DNA nucleoid shown in Fig. 5a, bacteria also contain ribosomes and plasmids within the cytoplasm. These are protein inclusion bodies containing nucleotide RNA in the ribosomes and additional DNA genes in the plasmids.
What are the 7 types of bacteria?
Bacteria are classified into five groups according to their basic shapes: spherical (cocci), rod (bacilli), spiral (spirilla), comma (vibrios) or corkscrew (spirochaetes) . They can exist as single cells, in pairs, chains or clusters. Bacteria are found in every habitat on Earth: soil, rock, oceans and even arctic snow.
What are the 10 types of bacteria?
- Deinococcus radiodurans.
- Myxococcus xanthus. ...
- Yersinia pestis. ...
- Escherichia coli. ...
- Salmonella typhimurium. ...
- Epulopiscium spp. The big boy of the kingdom – about as large as this full stop. ...
- Pseudomonas syringae. Dreaming of a white Christmas? ...
- Carsonella ruddii. Possessor of the smallest bacterial genome known, C. ...
What are the 3 types of viruses?
- Macro viruses – These are the largest of the three virus types. ...
- Boot record infectors – These viruses are known also as boot viruses or system viruses. ...
- File infectors – These viruses target .
What are 5 characteristics of viruses?
These are: 1) attachment; 2) penetration; 3) uncoating; 4) replication; 5) assembly; 6)release. As shown in , the virus must first attach itself to the host cell.
What do all viruses have in common?
All viruses contain nucleic acid, either DNA or RNA (but not both), and a protein coat, which encases the nucleic acid. Some viruses are also enclosed by an envelope of fat and protein molecules. In its infective form, outside the cell, a virus particle is called a virion.
Do viruses or bacteria reproduce faster?
Humans produce a new generation every 20 years or so; bacteria do it every 20 to 30 minutes, and viruses even faster . Because they reproduce so quickly, microorganisms can assemble in enormous numbers with great variety in their communities.
How do viruses replicate in the human body?
Viruses cannot replicate on their own, but rather depend on their host cell’s protein synthesis pathways to reproduce. This typically occurs by the virus inserting its genetic material in host cells, co-opting the proteins to create viral replicates, until the cell bursts from the high volume of new viral particles.
What is difference between bacteria and a virus?
On a biological level, the main difference is that bacteria are free-living cells that can live inside or outside a body , while viruses are a non-living collection of molecules that need a host to survive.
What are the 2 classifications of bacteria?
There are broadly speaking two different types of cell wall in bacteria, that classify bacteria into Gram-positive bacteria and Gram-negative bacteria .
Where is the most bacteria found in the human body?
Your gut is home to most of the microbes in your body, but your skin, mouth, lungs, and genitalia also harbour diverse populations. And as research continues into body biomes, it should reveal answers about how these microorganisms are promoting health or even disease.
What are 2 types of bacteria that make us ill?
Infectious bacteria (those that do make you sick) slip into your body and live among your healthy cells. Many emit chemicals called toxins, which can damage tissue. Streptococcus (strep), Staphylococcus (staph) and E. coli are some of the more commonly known bacteria that can cause infections.
