Ch. 3 : Handy Genes

This chapter was very informative but at the same time, it was pretty difficult to understand the concepts. By far it was the hardest chapter to understand. But it was still interesting with the similarities of the genes we have with other species. That fascinated me because I never knew we could have the same genetic recipe as fishes. Everything is too interesting because I realize that almost every kind of species can share the same genetics. Another interesting thing is that you can change the outcome of an embryo when adding chemicals to it. One thing about genes that is difficult to understand is how it turns on and off. I don't understand how genes can act mechanically like some kind of machine. This also leaves me with the question, "How does the genes know when to activate at the right time?" Also, with the ZPA, it was interesting to learn how the shape of the fingers can vary from the distance of ZPA. Shubin help my understanding with Summerbell's example with the foil. This show how important the ZPA was and even a slight mistake can cause a defect. Lastly, to know that we have a same hedgehog gene as the chicken and the fly fascinated me even more. And when the sonic hedgehog gene is not working properly a person can have fingers that look alike. Even though it's a little disturbing, it interests me. Although this chapter was a little confusing, I still learned a lot from it.

- Joo Won Jang