Heredity Study Biology 5 th Hour 2012
Abstract The traits that we tested against our family were the taste of PTC paper, if they have hair on their second digit of their finger, and if they have unattached or attached earlobes, and if they could roll their tongue in anyway. We have a big family and didn t get around to testing all of the traits that we wanted to. There were a ton of people that couldn t taste the PTC paper. There were very few who could taste it. Almost everybody in my family has unattached earlobes. Only four people that we tested had attached earlobes, and most of them were married into the family. Out of the thirty people that we tested only six of them could not roll their tongue. Most of our family can roll their tongue either hot dog style or clover-leaf style. When we tested for hair on the second digit of their finger, we concluded that almost every guy has hair there and barely and girls have hair on their fingers. Our family has the trait where they have lots of hair except for on their heads, so we predicted that it would turn out to be like that. As of the world population, we think our family is right there with the rest of the world. It looks as if our family got the dominant trait of having unattached earlobes. There were very few that got the recessive trait from their other genes. Almost everybody was able to roll their tongue and it was about even of how many boys and girls were able to. Errors could have gone wrong by them not being a blood-related relative.
Introduction What do you think genetic means? Genetics is the study of heredity. Heredity is the transfer of characteristics from the parent to their offspring. Hereditary traits are made by specific genes. The offspring gets one trait from the mother which is the egg, and one part from the dad, which is his sperm. When they reproduce, the genes segregate and go into different gametes. Your hair color, height, and chance of getting certain diseases are based on heredity. If it runs in your family you have a chance of getting that disease.
Background Tasting of PTC paper: The percentage of people who can taste PTC paper is 70%; the percent that cannot taste the PTC paper is 30%. If you can taste the paper, it shows a dominant pattern of inheritance. The ability to taste PTC goes with the ability to taste other bitter foods that do not happen naturally. They usually have toxins in them. The two commons forms are tasting an allele, and a non-tasting allele. The shape of a receptor protein determines how strong it can stick to the PTC. Everybody has two copies of genes, so whether you can taste the paper depends on if people find the taste bitter, or a little bit bitter, or really no taste at all. http://en.wikipedia.org/wiki/phenylthiocarbamide Attached or Unattached Earlobes: Having an attached earlobe is recessive, and having an unattached earlobe is dominant. Some people have one attached earlobe and the other ear is unattached. How does this happen? Well, one ear might have followed the dominant gene and the other one followed the recessive one. Another way to have this happen is if you are a chimera. A chimera is a person who has two groups of cells in them. Each cell has their own set of DNA. There is a big difference between the two sets of DNA. 25% of people have attached earlobes and 75% of people have free earlobes. http://www.thetech.org/genetics/ask.php?id=190 Ability to Roll Tongue: The ability to roll your tongue is dominant over not being able to roll your tongue. 65%- 85% of people are able to roll their tongue. There are more females that can do it compared to males. Tongue rolling is a two-allele trait. Each gene has two alleles. We all know that genes make proteins. There could be a gene somewhere in the genome that is able to block the action of the tongue rolling proteins made by the tongue rolling genes. That affects if you will be able to roll your tongue or not. They say that if you are able to roll your tongue, you could have a modifier gene. http://www.brighthub.com/science/genetics/articles/35598.aspx Mid-Digit Hair:
Mid digit hair genetics are determined by autosomes. Having hair on your mid-digit finger is said to be dominant. D0, D1, D2, D3, D4, are examples of the five multiple alleles. This refers to the number of fingers having mid-digit hair. If you have D0D0 means that it is the absence of mid-digit hair. 40% of Japanese people, and 70% of Germans have hair on their middle digit finger. They took a survey in Japan testing about 7,500 people and at least 24% of those people had hair on their mid-digit finger. http://udel.edu/~mcdonald/mythdigithair.html
Methods Hypothesis: We think that less people will be able to taste the P.T.C. paper more than people who will be able to. More people will have unattached earlobes. Sam thinks that almost everybody will be able to roll their tongue in some way. My opinion is different. I think that more people won t be able to roll their tongue at all. We both think that there will be a lot of people who will have hair on the second digit finger. We highly doubt that there will be anybody in our family who won t have hair on their second digit finger. Procedure: We plan on testing our traits by going to each of their houses or calling them on the phone. For each one of the houses we visit, we will be looking at all the traits that they have. If we can t go to their house we aren t going to have them taste the P.T.C. paper because then you couldn t test if they could taste it or not. If we end up calling them on the phone, we will have them test the easier ones. They can look in a mirror for themselves to determine which traits they have. Controlled: The controlled variable will be the blood-related relatives. We will compare these trait results to the nation s results. We will compare these results to the non-blood relatives that are part of our family by marriage. Variables: Our variable will be the relatives that are not blood-related to us. Their results will probably differ from the relatives that are blood-related. If one of our blood-related cousins is pregnant, she might not be able to taste the paper as well as other family members should be.
Family: Taste of PTC paper: Free or Attached Earlobes: Ability to Roll Tongue: Hair on 2nd Digit Finger: Blood related/married in Grandma Yes Unattached Yes Yes blood related Jim didn't test Unattached Yes Yes blood related Christine Yes Unattached Yes Yes married in Kieran No Unattached Yes Yes blood related Alex Yes Unattached Yes Yes blood related Joey Yes Unattached Yes Yes blood related Keith No Unattached No Yes blood related Jeremy No Unattached Yes Yes blood related Cork Yes Unattached Yes Yes blood related Mikayla No Attached Yes No blood related Connor No Unattached Yes Yes blood related Christina didn't test Attached Yes No married in Janai No Unattached Yes No married in Mo No Unattached Yes Yes blood related Bone No Attached Yes No married in Jason didn't test Attached Yes Yes blood related Lindsay didn't test Unattached Yes No married in Brad didn't test Unattached No Yes blood related Cassie didn't test Unattached No No blood related Ryan didn't test Unattached Yes Yes married in Mike No Unattached Yes Yes blood related Jill Yes Unattached Yes No married in Sam Yes Unattached Yes Yes blood related Max Yes Unattached No Yes blood related T.J. No Unattached Yes No blood related Chris No Unattached Yes Yes blood related Judy Yes Unattached Yes No married in Ben No Unattached No No blood related Ryan Yes Unattached Yes No blood related Eryn Yes Unattached No No blood related Total Amount: % of each World % 11 Yes, 12 No 48% yes, 52% no 70% can, 30% can't 4 Attached, 26 Unattached 13% attached, 87% Unattached 75% Unattached, 25% Attached 24 can roll, 6 can't roll 18 Do, 12 Don't 80% can roll, 60% Do, 40% 20% can't Don't 85% can roll, 15% can't Germans: 70% do, 30% don't Japanese: 40% do, 60% don't
Discussion Even if the people are married in they still have a lot of the same traits. There were only a few that didn t have unattached earlobes. Like Christina is married in and she has attached earlobes so her daughter, Mikayla also has attached. A lot of our family members who are married in have no hair on the second digit of their finger. A lot of the people that are married into our family are girls because we have eight uncles and only two real aunts. The world percentage is way higher for people who can taste PTC paper than people who can in my family. My family s percent is closer than the world s percentage. For unattached earlobes the percentages are a lot alike. More people have unattached earlobes than attached earlobes in my family and in the world s population. The percentages are very close in being able to roll your tongue. Our family s percent is 80% and the world s is 85%. Since we couldn t find any world percentages for having hair on your second digit finger, I will compare our family s results to the Germans, and the Japanese. Our family s percentages are really close to the German s but not the Japanese. We are closer to the German s more than the Japanese.
REFERENCES http://www.koshland-science-museum.org/teachers/inventory_of_your_traits.pdf http://www.brighthub.com/science/genetics/articles/35598.aspx http://udel.edu/~mcdonald/mythdigithair.html http://library.thinkquest.org/19037/heredity.html http://dictionary.reference.com/browse/genetics http://.omg-facts.com/view/facts/14982 http://www.uni.edu/walsh/genetics.html http://en.wikipedia.org/wiki/phenylthiocarbamide