Viruses
Why are viruses considered to be dead
Viruses are considered to be dead because they lack properties that scientists associate with living organisms. Primarily, they lack the ability to reproduce without an available host cell, and don't use the typical cell- division approach to replication.
8 Characteristics of life:
8 Characteristics of life:
- All living organisms are composed of cells
- All living things consume energy
- All living things respond to their environment
- All living things grow
- All living things reproduce
- All life ends
- All life adapts to it's environment
- All living things must maintain internal and external homeostasis
Lysogenic cycle |
Lytic cycle |
In the lysogenic cycle the genetic material of the bacteriophage, called a prophage, can be transmitted to daughter cells at each subsequent cell division, and a later event can release it, then it goes into the Lytic cycle.
|
The lytic cycle results in the destruction of the infected cell and its membrane. Also known as Lysis meaning to break or burst.
|
The three ways the body protects itself from pathogens
The three ways the body protects itself from Pathogens are your skin, Reverse Phagocytosis, and System Responses like Interferon and Antibodies.
Binary FissionFission is the division of a cell into two or more parts which leads to the regeneration of those parts into separate cells. Binary Fission produces two separate cells, populations, species, etc. Reference to the picture below for the steps involved with Binary Fission.
|
ConjunctionBacterial Conjugation is a mechanism of horizontal gene transfer between bacterial cells by direct cell-to-cell contact through a bridge-like connection between the two cells. Reference to the picture below for the steps involved with Conjugation.
|
How bacteria can alter the genetic information
The binding of DNA fragments to the bacterial cell surface, the uptake of DNA into the cytoplasm, and the incorporation of the imported DNA into the bacterial chromosome
Evolution of Antibiotics relating to "super bugs"
Antibiotic resistance arises as a result of natural selection . Since bacteria reproduce rapidly, resistance can arise quickly. Those antibiotics resistant will remain after treatment and can continue to divide. An example of antibiotic resistance can be seen with Penicillin, some bacteria can produce an enzyme called Penicillinase which breaks down Penicillin before it can take effect. Another mechanisms of resistance include the evolution of a capsule that is resistant to antibiotic, and cell membranes becoming less permeable to antibiotic. Bacteria can spread resistance genes between each other by bacterial conjugation where two cells join by their pilli and exchange plasmids which often contain genes for antibiotic resistance.
Sources
https://orderantibioticswithoutprescription910.wordpress.com/
http://www.ncbi.nlm.nih.gov/books/NBK8439/
http://www.emedexpert.com/classes/antibiotics.shtm
http://www.ncbi.nlm.nih.gov/books/NBK8439/
http://www.emedexpert.com/classes/antibiotics.shtm