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Unit 7 Exercise 1 Reaction Paper

Decent Essays

Answers should be about 50-100 words in length and in your own words.

1. Describe the process by which cholera toxin leads to severe fluid and electrolyte loss during diarrhea.

The cholera toxin is produced by the cholera bacteria Vibrio cholera. The toxin attaches itself to receptors on the cells that make up the small intestines. In doing so, cyclic AMP (cAMP) is activated and there is also an increase in the number of cAMP molecules within the cell. A special chloride ion channel called CTFR normally allows chloride ions flow out of the cell, leading to a higher concentration of chloride ions outside the cell. But when CTFR channels are activated by cAMP, they stay open and the negatively charged chloride ions within the intestinal cells move …show more content…

How do these two general observations help explain why such diseases so commonly affect humans?

GIT diseases are ultimately self-limiting and nonfatal as long as fluids are replaced. However, GIT diseases commonly affect humans due to a number of reasons:
Humans need to eat, especially after expending energy on activities necessary for its survival. Since humans are not autotrophs, they depend on other organisms for the food they eat. Occasionally, in the course of finding food, humans may ingest pathogenic organisms that may cause GIT diseases.
Also, many pathogenic microbes exist in low-energy inactive states, possibly due to the fact that energy sources in the natural environment occur in somewhat complex forms that may need work for the microbes to break down. Humans, on the other hand, have enzymes that play an important role in breaking down compound energy sources. This further explains why ingested microbes easily switch to parasitic forms as soon as they are within the GIT of human hosts. Once within the human hosts, these microbes compete with human cells for broken down and simplified

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