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Student questions that got me researching:

Question: "How does the body know how much bile to produce?" -Logan Michael

Answer: The short answer is: hormones. Of course, bile production is far more complex than I present in class. It is a mixture of compounds: water, cholesterol, bile salts, lecithins, and bilirubin to name a few. It is our main mechanism for excreting cholesterol. It also emulsifies fats for more efficient digestion. Bile is stored in the gall bladder where it is concentrated. Disruptions in this process can lead to some compounds to come out of solution forming "stones". When we eat a fatty meal, the partially digested fats hit the top of our small intestine and stimulates cells to produce the hormones secretin and cholecystokinin (CCK). The secretin stimulates the pancreas to secrete it's juices and the liver to make more bile. The CCK stimulates the gall bladder to squeeze its concentrated bile into the small intestine.

Source(s): The definitive resource is https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2748197/. For a more digested version (pun intended), check out http://www.vivo.colostate.edu/hbooks/pathphys/digestion/liver/bile.html

Question: "Was Mendel the guy who came up with Punnett squares?" -Kyle Nagel

Answer: Structures that have Capitalized names are usually named after the person who first described or came up with the device. In the case of Punnett squares, the guy was Reginald Crundall Punnett who published Mendalism in 1905. He was one of the first researchers to read Mendel's papers and did more work breeding peas and chickens and used his squares to show the possible allelic combinations.

Sources: wikipedia.com and a scanned copy of Mendelism, by R. C. Punnett found at http://books.google.com/books?id=Uuk3AAAAMAAJ&pg=PA1&dq=punnett#v=onepage&q=&f=false


Question: "Where to new corals get their symbiotic zooxanthellae from?" -Victoria Freeborn

Answer: Although they can be tugh to detect, there are free-living forms of zooxanthellae found in low densities in the water and in higher densities in the sediment, especially near reefs. Corals, both new and ones that have expelled their symbionts can become populated (or re-populated) when endodermal cells engulf the zooxanthellae. Not all corals have the symbionts. Some non-corals harbor the zooxanthellae as well.

Source(s): Pasternak, Zohar, et al (2006) Host-finding behaviour and navigation capabilities of symbiotic zooxanthellae Coral Reefs 25:2

Question: "Can you have too much myelin"

Answer: Yes. There is a condition known as tomaculous neuropathy. A tomacula is a section of nerve axon that has too much myelin. This can put pressure on other nerve fibers and negatively affect their function casing numbness, tingling and cognative issues depending on where the tomacula is. The cause seems to be genetic.