Smallpox is a disease caused by a specific virus, while the common cold can be caused by over 100 different viruses. explain why it is possible to develop a vaccine to prevent smallpox, but it is difficult to develop a vaccine to prevent the common cold. in your answer be sure to: • identify the substance in a vaccine that makes the vaccine effective • explain the relationship between a vaccine and white blood cell activity • explain why the response of the immune system to a vaccine is specific • state one reason why it would be difficult to develop a vaccine to be used against the common cold?

1. There is a small sample of the disease that's being tried to prevent so that the body can get used to fighting it.

2. In the vaccine there is a small sample of a disease that the vaccine is being used to prevent. The white blood cells fight harmful bacteria and so prevent diseases.

3. A vaccine works by training the immune system to fight viruses or bacteria.

4. The antigenic variability of the virus and other viruses and bacteria acts as infective agents.

a few examples of ethical concerns involving genetically engineering of humans include

-privacy of genetically tested people

- potential side effects

-long term effects

in the year 2850, humans successfully colonized mars. the martian modules that were constructed could hold only a small population of people. it is now a century later, and the population on mars has grown to 600 people. of the current mars population, 45 people express the recessive phenotype for phenylketon- uria (pku) syndrome (pp genotype).

explanation: