Biology of Humans 6th Edition by Judith Goodenough,Betty McGuire

Exercise 8

We have seen that genes produce proteins that play a structural or functional role in the cell. Gametes are created by meiosis, and a random assortment of maternal and paternal chromosomes of each homologous pair are distributed to the gametes. When gametes fuse at fertilization, a zygote is created that contains homologous pairs of chromosomes, one member from the mother and the other from the father. The zygote undergoes many mitotic divisions in which genes are replicated and identical copies of chromosomes are distributed to daughter cells. Identical twins form from a single zygote, and the structure of their DNA is identical. Fraternal twins develop from different zygotes and, therefore, they share only 50% of their DNA. You have undoubtedly noticed that mosquitoes are attracted to some people more than others. Skin scent is partly responsible for attracting mosquitoes. Researchers hypothesized that skin scents that attract mosquitoes are genetically based.1 The following is an excerpt from Rob Stein on the National Public Radio report "Why Do Mosquitoes Like to Bite You Best It's in Your Genes," April 22, 2015, 4:08 p.m. ET. You can read the entire article at http://www.npr.org/ sections/health-shots/2015/04/22/401469931/why-do-mosquitoeslike- to-bite-you-best-its-in-your-genes. "... researchers brought 18 pairs of identical twins and 19 pairs of fraternal twins into the lab. Each person stuck a hand in one of the short arms of a Y-shaped plexiglass tube, as air was blown past the hand, toward 20 female Aedes aegypti mosquitoes clustered at the long end of the Y. Once released, the insects could choose between the twins-to fly upwind, along either side of the Y, presumably following the odor of the person they were most attracted to. (The scientists used a new batch of hungry mosquitoes in each trial, and also compared the results to trials that involved 'clean air' and nobody's hand.) There was essentially no difference in the mosquitoes' response to genetically identical twins, the scientists found, but quite a bit of difference in their response to fraternal twins, who are as genetically different from each other as any other pair of siblings."
Use at least three reliable sources to find additional factors that might cause a person to attract (or repel) mosquitoes. Cite your sources and explain why you chose them.