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Scientists Help! Genetics?

Scientists Help! Genetics? Topic: Examples of test case scenarios
June 26, 2019 / By Trisha
Question: 1. What is the difference between alleles and genes? 2. How can a test cross reveal the genotype of a pea plant with round seeds. 3. Difference between imcomplete dominance and codominance. 4. Two examples of traits that are influenced by environmental conditions. 5. How a genetic disorder can result from a mutation. 6. Describe how males inherit hemophillia.
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Best Answers: Scientists Help! Genetics?

Sam Sam | 5 days ago
1- Scientifically speaking, gene is a locatable part of genome in which the alleles for an inheritable trait reside. An allele is one member of a pair or series of different forms of a gene. Think of them this: An allele is like a house and a gene is the street address of that house (where the house is located). 2- If you have a pea plant with dominant phenotype and you need to figure out its genotype, you cross it with a plant with recessive phenotype. The results will be either one of the following scenarios: A- All of the F1 generation have dominant phenotype: in this case the unknown parent must have been homozygous for the trait that you are testing for. B- Some of the F1 generation have dominant phenotype and some have recessive phenotype: In this case you know that the unknown parent must have been heterozygous for the trait in question because the only way to have recessive phenotype in F1 generation is that the F1 individuals with recessive phenotype must be homozygous for that trait. And since each individual gets one allele from each parent, the the unknown parent must have had 1 recessive trait. As for the individuals in F1 generation with dominant trait, they all are heterozygous (Do you know why?) 3- Incomplete dominance (sometimes called partial dominance) is a heterozygous genotype that creates an intermediate phenotype. It is when you cross a red carnation and a white carnation and you get a pink carnation Co-dominance is when both alleles will show their effect in the phenotype. in co-dominance neither phenotype is recessive. An example of this is roan horses. 4- Sorry, I can't help with this one. 5- Mutation is the only source of creating new variations. Most mutations are harmful and many embryos that carry a mutation die before they are turned into a fetus. A mutation changes the sequence of DNA of a gene which can change the protein that, that gene codes for. If an embryo with a harmful mutation develops into a fetus and then to a baby, the baby will have some genetic disorder. 6- Hemophilia is a recessive sex related disease. The gene for most of the sex related diseases are located on X chromosome. If a female carrier of the gene gets pregnant by a healthy male, all of their daughters will be health but 1/2 of them will be carriers of the gene (because the health X chromosome of dad will mask the unhealthy chromosome of mom, therefore non of the daughters will show the signs of the disease). Half of their sons will also be happy (the ones that inherit the healthy X chromosome from their mom) but the other half will be hemophiliac (the ones that inherit the unhealthy X chromosome from mom; dad's Y chromosome can't mask the X chromosome completely).
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We found more questions related to the topic: Examples of test case scenarios


Sam Originally Answered: For years scientists used the WRONG Speed of Sound! Are there any others? Why do scientists "Trust"?
You have to be careful of the distinction between something being utterly wrong vs. being a little out of whack. If the discrepancy had been a large one it would surely have been found much earlier. I imagine there are many complicating factors in measuring the speed of sound in air -- for example, are you talking about "dry" air or air with some amount of water vapor in it? I bet that makes a difference. And I bet the small discrepancy the news item mentions was smaller than variations in the speed of sound engineers encounter when they deal with everyday situations. There was an article in the Am. J. of Physics recently that discussed an experimental error in Millikan's measurement of the charge on the electron. Another type of experiment gave a slightly different value (and it turned out to be much closer to today's accepted value), but it took years to remove the bias toward Millikan's value because his effort was well respected. A much bigger issue of what is really true vs. what we think is true is what Thomas Kuhn talked about in his book, The Structure of Scientific Revolutions. He argues very convincingly that one culture can hold a completely workable world view that suddenly gets overturned by a totally new way of looking at things. He called this a 'paradigm shift.' Many of these paradigm shifts have happened in the past, so who's to say it won't happen again? My gut feeling is that we are closer to the real truth about the world now than ever before, but I'm also sure that there will be surprises ahead. I hope we get to witness some of them.
Sam Originally Answered: For years scientists used the WRONG Speed of Sound! Are there any others? Why do scientists "Trust"?
That's why scientists continue to do experiments on things previously "proven." It's also why scientific journals are "peer-reviewed." Errors occur - we're human - but they eventually get discovered because people keep checking. When two scientists disagree, experiments are designed to let Nature settle the issue. If you get a wrong answer from your experiment it's one of these things: * The experiment was designed wrong (measured the wrong thing, etc.) * The experimental device was improperly calibrated. * Some variable that affected the outcome was not controlled. * An error crept into the data. * The analysis contained an error. * A new and previously unanticipated phenomenon is affecting the results. This is why journal articles are so carefully written. They include the scope of the study, the exact experimental setup, the values of the parameters involved, the analysis including mathematical derivations, the raw data, and the conclusions. Anyone can then reproduce the experiment or question the assumptions. BUT, you can't get ANYTHING done if you have to check EVERYTHING. And since most stuff has been checked over and over, most people accept previous results as-is. So it can take time for small discrepancies to show up.
Sam Originally Answered: For years scientists used the WRONG Speed of Sound! Are there any others? Why do scientists "Trust"?
A good scientist will never "trust" anything. Science is the pursuit of knowledge and that is a neverending quest. We generally accept that c (the speed of light) is the absolute cosmic speed limit but Einstein wasn't perfect and c may someday turn out to be just our imperfect perception of the universe. We learn new things all the time and the errors discovered just goes to prove that science works when we accept the fact that we can and will make mistakes. Science by its nature is self-correcting and that's the way it should always be.

Nikkole Nikkole
Well I had a genetics final exam today and i'll answer the ones i can 1) A gene is a physical part of a chromosome which codes for a specific polypeptide. The allele is a symbol for the gene which is used is crossing and inheritance problems. 2) A test-cross means that you are crossing the desired pea plant with a plant with all recessive traits. 3) Incomplete dominance means that for a heterozygous phenotype we get both alleles expressed, for example Bb, if B=black and b=white, due to incomplete dominance the phenotype would be a mix, or grey. Codominance means you have both Alleles expressed as in blood. AB genotype means you have bloodtype AB 5) If a mutation occurs on DNA, the resulting mRNA will be defective, and thus the protien translated will be defective which is the genetic disorder.
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Nikkole Originally Answered: Scientists in scientists vs shamans?
A scientist uses the scientific method, which formulates a hypothesis and then -- most important -- TESTS to see whether this is correct. If it seems to be correct, the scientist then repeats the test to see if this can be verified or if it was a fluke, or due to chance, etc. Sometimes a test will require the hypothesis to be modified in some way, in fact, this is normally what happens. This is how science grows. The hypothesis is modified and a new test is devised. The shaman uses magic. For example, suppose you are outdoors and want to catch a fish. The scientist decides that perhaps hanging a bit of meat on a string will work. She tries different types of strings with different types of meat hanging in different streams on different days, or perhaps different times of day, and sees which one catches the fish. When she thinks she has it figured out, she prepares a large number of that type and tries them out (the repeated test). If it works, she does it on a regular basis. The shaman does a fish dance, moving his mouth like a fish does, sings fishy songs, and carves a fish symbol into a tree near a stream. "Okay, now, fish!" he calls into the water. "Come to my hands!" Which one is going to catch more fish?
Nikkole Originally Answered: Scientists in scientists vs shamans?
maximum Christians have faith in Scientists and a few scientists are Christians, besides what form of Christian? Catholics are exceedingly liberal on scientific subject concerns for the main section. I mean we invented the technology of biology and genetics, and Pope Pius X certainly supported the massive Bang concept. the sole disconnect is they do no longer want to pay attention we got here from apes, that God created human beings seperately yet they do have faith in evolution/dinosaurs/uni-to-multicellular evolution,etc. maximum Protestants on the different hand might look at some imprecise Bible quote and inform you the way the Earth is in actuality flat and how the sky is blue with the aid of basin above it has water and how they have faith existence could no longer evolve consistent with A and how cells are a lie consistent with B, etc. standard, I mean i'm no longer an athiest yet technology might probable win, the sole time a Christian has ever beat a Athiest Scientist under expert standards became into this Anthony Flew vs. William Lane Craig debate (a in demand scientist and apologist respectively), its on YouTube i think of.

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