Human Disease and Their Control

Biology (B3A) Assignment
Human Disease and Their Control

follow up questions
1a) When people refer to pathogens, they are talking about bacteria that cause disease.
1b)The toxins actually excreted by the pathogens are the main cause of diseases although thetoxins are only by-products of the pathogen\'s metabolism.

2a)In most cases, the toxins excreted by the pathogens find there way into the circulatory system. Thus, sometimes, the infection is caused somewhere else from where the toxins were excreted. An example of this would be Rheumatic fever. The toxins that cause this disease is excreted by the pathogen as a by-product of metabolism. Usually, the pathogens that cause rheumatic fever is located in the throat. As the toxins enter the circulatory system, it travels along the system and eventually causes an infection in the heart vavles.
Yet another example of where the disease is in a different location then where the toxin was released is Dipheria. The pathogen that causes Diptheria is usually located in the throat. As the toxin is released, it travels all the way to affect limb muscles and the heart.
2b) Examples of where the disease is at the site of the bacteria could be Tetanus and Tuberculosis. The tetanus bacteria releases a deadly toxin which can affect the whole body which causes paralyzation. As it affects the whole body, the disease would most likely be caused at the location of the bacteria. This disease will not always paralyze your whole body but most of the time, it would paralyze your jawbone. Thus tetanus is also known as lockjaw. Tuberculosis as a disease that affects the lung cells. The tocins also affect the lung cells. Therefore, the pathogens for tuberculosis could be found near the site of disease.

3a) In our environment, we encounter all sorts of micro-organisms. Sometimes these air-borne diseases are pathogens and could cause and make one sick. Examples of air-borne pathogens that cause diseases are the ones that cause whooping cough, scarlet fever, and the mumps.
3b) An example for this kind of transmission would be the kind of pathogens found in feces. Typhoid fever is one of the kinds of diseases that are transmitted through water as these pathogens are found in feces. The feces released would sooner or later find its way back into drinking water. Then, as the pathogens enter the drinking water, they come out and just like float around until a new host comes. When the new host comes and drinks from the water source, the pathogens take this oppertunity to enter the host. Once the pathogens enter the body, the host would be infected.




4a) Besides transmitting disease through everyday drinking water and the air, another way of transmitting diseases are by contact. Chicken Pox and Small Pox are some of the many diseases that can be caused by contact.
4b) Veneral diseases like gonorrhea and syphilis can also be transmitted by contact.

5a) An example of a disease that can be transmitted if there is a wound would be our very familiar Tetanus. An example of how someone would acwuire tetanus from a wound would be like this:

The construction worker moves around a lot and works very hard. Down on the floor is a tetanus infected nail. As the worker is too busy caring for his job, he accidently steps on the nail and gives the tetanus bacteria a chance to get into the body. The tetanus would be succesful from coming from the nail and going to the host. As the wound would close very quickly, this provides an oxygen free atmosphere in which the tetanus bacteria could start to get active.

6a) Immune carriers can be classified as those who have recovered from a certain disease and is immune to it, but still carries the pathogens. The immune carriers show no indecation of a disease with no symptoms, but this carrier can still trnasmit these pathogens to others.
6b) One major disease carrier is the Anthropod. They pick up the pathogens in their food, where they walk and other places. As they carry the disease, they move to other places either for food or shelter purposes. When they bite or sting other organisms, the disease is trnasmitted through the anthropod and infects a new host.

7) The skin is the main protector from pathogens. The first line