Answer to Question 1
Answer: Viruses are very simple microorganisms that need a host cell to reproduce. Once they take over a cell and reproduce, they kill the host cell, thus, are known as parasites. While they cannot survive long outside of a host cell, once inside, they multiply quickly. Antibiotics are useless with a viral infection. Examples of viral illnesses are the common cold, influenza, mononucleosis, varicella, H1N1, H1N5, SARS, West Nile virus and Hantavirus. Bacteria are single-celled organisms that can exist either independently or as parasites and can reproduce on their own. Most bacteria are helpful; these are referred to as probiotics. Only 1 of the planet's bacteria are pathogenic. These can release toxins in to our tissues or can directly damage cells. Antibiotics are used to treat bacterial infections. Examples of bacterial illnesses are meningitis, staph infections, including MRSA, Streptococcus infections, Lyme disease, tuberculosis, and UTIs.
Answer to Question 2
Answer: The chain of infection is comprised of six conditions that have to be met in order for an infection to spread in a population. Disruption of any of the links in this chain reduces the likelihood that an infectious disease will develop into an outbreak. The six conditions are a pathogenic microorganism, a reservoir, a means of escape, a mode of transmission, a means of entry, and a susceptible host.
Examples of intracellular receptors
Differences in embryonic development between protostomes and deuterostomes.
Examples of sterilizations and disinfection processes
Protein Evolution: Myoglobin and Hemoglobin as Examples
skull differences
Examples of Conditions Detected by Prenatal Genetic Screening Methods