1.Describe three conditions that create opportunities for pathogens to become harmful in a human. There are many conditions that create opportunities for pathogens to be harmful for humans. The first is when the immunity has already been compromised by an infection. In cases like this, there is the chance of other pathogens to cause opportunistic infections in such host. Another condition is if the human host does not keep proper personal and environmental hygiene. Many pathogens thrive in dirty environments and if an individual refuses to keep proper environmental hygiene, such individual is increasing the chances of him being infected by pathogens. Finally, many pathogens are transmitted by vectors and if humans do not take the care to curtail the activity of pathogen vectors, humans are more liable to be infected by the pathogens that these vectors help to transmit. 2.In order for a pathogen to cause disease, describe three things that must happen. The first is that the host needs to be exposed to the pathogen. This could happen in variety of ways, such as being exposed to infectious substances, or coming in contact with infected body fluids of an infected person. The second is that the pathogen must come in contact with the epithelial surface of the host. …show more content…
When larger substances, such as disease vectors or foreign bodies that are laden with pathogens, try to get into the respiratory tract, the hairs in the nose prevent the much larger substances from advancing far into the respiratory tract. Smaller substances that can bypass the air in the nose are trapped by mucus lining the epithelium of the respiratory tract. After this, the trapped foreign bodies and pathogens are forced up the respiratory tract into the pharynx and then swallowed into the alimentary