How does Cholera work?
Cholera works by releasing a toxin in the lumen. It causes chloride channels of the intestinal epithelial cells to open which in turn causes cholride ions to move along its concentration gradient into the lumen of the small intestine. This causes water to move via osmosis into the lumen of the small intestine (as the water potential of the lumen becomes more negative than the water potential of the epithelial cells) causing lots of water to be lost from the body. This causes severe dehydration which is how Cholera works.
TK
Related Biology A Level answers
All answers ▸Outline the process which occurs when an action potential arrives at a synapse
Humans and grasshoppers have very similar percentages of each base in their DNA but they are very different organisms. Use your knowledge of DNA structure and function to explain how this is possible (2 Marks)
In a population of deer there are two alleles, p and q. Individuals with allele p are faster than those with allele q and so are better at avoiding predation by wolves. Explain how natural selection will affect the characteristics of the deer population.
What are the different roles of synapses in the nervous system?