We used Brassica rapa, a fast plant the rapidly reproduces, in an experiment that we performed a monohybrid cross and a dihybrid cross. We hypothesized that in the monohybrid cross, the F2 generation of Brassica rapa will follow Mendelian inheritance patterns and show a phenotypic ratio of 3 anthocyanin positive to 1 anthocyanin negative. If the F2 generation follows Mendelian inheritance patterns, then out of 1105 plants, 828.75 will be anthocyanin positive and 276.25 will be anthocyanin negative. For the dihybrid cross we hypothesized that the F2 generation of Brassica rapa will follow Mendelian inheritance patterns and show a phenotypic ratio of 9 Anthocyanin positive dark green to 3 anthocyanin positive yellowish green to 3 anthocyanin …show more content…
These results gave us a chi-square statistic of .06787 and with a degree of freedom of 1, this .06787 is below the critical value of .05 so therefore the results do follow typical patterns of inheritance. This means that our hypothesis for the monohybrid cross was correct, the F2 generation follows Mendelian inheritance patterns. In the dihybrid cross, the observed results were 487 or 55.7 % of the plants had anthocyanin dark green leaves, 166 or 19% of the plants had anthocyanin yellowish green leaves, 136 or 15.6% of the plants had no anthocyanin dark green leaves, and 85 or 9.7% of the plants had no anthocyanin yellowish green leaves. These results gave us a chi-square statistic of 21.703 and with the degrees of freedom at 3 this is still well below the critical value of .05 and therefore the dihybrid cross does not follow typical patterns of inheritance. This means that our hypothesis for the dihybrid cross was rejected, the F2 generation of Brassica rapa did not follow Mendelian inheritance patterns. The results show that the monohybrid cross did follow Mendelian inheritance patterns, while the dihybrid …show more content…
This information supports our hypothesis for the monohybrid cross, but it does not support our hypothesis for the dihybrid cross. In the monohybrid cross, it was expected that we would get a phenotype ratio of 3 plants with anthocyanin for every 1 plant with no anthocyanin. The plants with anthocyanin were easy to differentiate because of the purple color that is shown in the phenotype of plants with anthocyanin in them (Webb 2014). The results we observed were relatively close to this ratio, and the chi-square statist tells us that the monohybrid cross did follow mendelian inheritance patterns. In a different experiment done with Brassica rapa, it was found that when a set of plants with anthocyanin present were crossed with a set of the same species of plant but without anthocyanin present, the phenotypic ratio observed was 3 to 1 (Hayashi et al. 2010). This information just reinforces the idea that a monohybrid cross between Brassica rapa with anthocyanin and without anthocyanin does produce a F2 generation that follows Mendelian inheritance patterns with a 3 to 1 phenotypic ratio. The dihybrid cross we conducted was done with the anthocyanin gene, and the color gene. The dihybrid cross did not follow Mendelian inheritance patterns, so this leads us to believe there must have been a source
This meant that we had to reject our hypothesis for the dihybrid cross which stated that there would be no difference in the observed and expected values. This showed that the F2 generations did not follow Mendelian genetics because it did not express a 9:3:3:1 phenotypic ratio. In both our F1 and F2 generations, we had to reject our hypotheses because they did not follow the Mendelian genetic inheritance pattern show by our results above. Because both the F1 and F2 generations of Brassica rapa failed to follow the Mendelian genetics inheritance pattern, there could have been some biological errors that cause this to happen. An example of this is that maybe not every single plant got the exact same amount of water or same amount of sunlight, causing the plants to grow differently and therefore deviate from the Mendelian’s law of inheritance. To prevent this from happening in the future, what could have been done was measure out the amount of water each plant got rather than just watering each plant casually. Also, for the amount of sunlight, steps could have been taken to ensure that each plant would get the exact same amount of light and not get different amounts just because of where they were
Test 4: All three phenotypic frequencies saw a reduction in their number as the homozygote fishes saw a reduction in their number and were not able to pass on their alleles to create either their colored fish or a heterozygote. Both yellow and blue allele frequencies decreased by the same
...ough genetic variability is generally a good quality, sometimes plant characteristics that are considered favorable by commercial propagators can be lost through genetic mutation during sexual reproduction of seed propagation. Also, sexual propagation through seeds is not always feasible for commercial propagators because of the length of time from germination until you have a fully developed plant (Horticulture, 2014).
...e been beneficial to the experiment. An error may have occurred due to the fact that measurements were taken by different individuals, so the calculations could have been inconsistent.
Thomas R. Warne, Leslie G. Hickok and Rodney J. Scott. (1988). Botanical Journal of the Linnean Society. Characterization and genetic analysis of antheridiogen-insensitive mutants in the fern Ceratopteris. 96 (1), 371-379.
An individual can be homozygous dominant (two dominant alleles, AA), homozygous recessive (two recessive alleles, aa), or heterozygous (one dominant and one recessive allele, Aa). There were two particular crosses that took place in this experiment. The first cross-performed was Ebony Bodies versus Vestigle Wings, where Long wings are dominant over short wings and normal bodies are dominant over black bodies. The other cross that was performed was White versus Wild where red eyes in fruit flies are dominant over white eyes. The purpose of the first experiment, Ebony vs. Vestigle was to see how many of the offspring had normal bodies and normal wings, normal bodies and vestigle wings, ebony bodies and normal wings, and ebony body and vestigle wings.
Throughout life there will always be obstacles to overcome. Whether it be personal, work related, or just trying to figure life out. There is not one person who is immune to these things. Unfortunately, there is not one person who is immune to discrimination either, which is why we, as human beings, must make a greater attempt to recognize the differences every individual has to offer, and embrace whatever it is to it’s full potential. Many feel the pressures that womanhood presents, for instance. Not to say there isn’t burdens that are exhibited with manhood, but there still remains some hefty barriers on the road to 21st century equality. It is a fact that men are met with greater confidence in the workplace, while women remain severely underrepresented
As a result of these factors, the flora has adapted to these conditions in a variety of ways including their shape, leaf type, root system, and color. One of the most prominent adapt...
After reading and annotating Marigolds by Eugenia W. Collier, I learned that there are some things we don’t know or realize when we are a child. When we become a woman, we have a different perspective on things. That is what Eugenia learned by the end of the story. Once she ruined all of Miss Lottie’s marigolds, she immediately felt guilty. Miss Lottie stood there with no anger on her face, just disappointment. Eugenia said that was when she saw her childhood fade and womanhood start to begin. Once she began womanhood, she learned that those flowers were precious to Miss Lottie and she was tying to make some beauty out of her shanty house. She viewed Miss Lottie as “… only a broken old woman who had dared to create beauty in the midst of ugliness
In order to figure out the genes responsible, there are several other factors that must be determined. These factors include the number of genes involved, if each gene is x-linked or autosomal, if the mutant or wild-type allele for each is dominant, and if genes are linked or on different chromosomes. Proposed crosses include reciprocal crosses between the pure-breeding mutants of strains A and B with the wild-type will help determine if the genes or sex-linked or autosomal, in addition to which alleles are dominant (8). Another proposed cross includes complementation crosses between pure-breading mutants from strains A and B to determine if one or two genes are involved (8). Furthermore, testcrosses between F1 progeny and pure-breeding recessive mutants from strains A and B, which will help determine if genes are linked on the chromosome or if they assort independently (8). These proposed crosses are shown in the attached
This experiment was performed to test two hypotheses concerning the plant hormone gibberellic acid and a mutant rosette shaped phenotype of the plant Brassica rapa. This experiment was done in order to test the effects o gibberellic acid on plants and its effect on rosette shaped complexes. The two hypotheses in this experiment are as follows: Hypothesis number one states that Gibberellic acid allows for stem elongation in plants. Hypothesis number two. The rosette complex in the rosette phenotype plant contains less gibberellic acid naturally and therefore grows shorter.
Mendel’s law of segregation states that offspring receive only one of two alleles of a gene from the parent (Brooker et al. 2014). This means that utilizing a monohybrid cross where each parent has both a dominant allele of a gene and a recessive allele, that by producing offspring of these plants, a predictable outcome of trait inheritance should be observed (Brooker et al. 2014). This experiment investigated the inheritance of anthocyanin in Brassica rapa.
The idea of the project was to experiment breeding Drosophila Melanogaster (fruit fly) to figure out if certain genes of that species were sex linked or not (autosomal). A mono-hybrid cross and di-hybrid cross was performed. For the mono-hybrid cross, white eyed female and red eyed male were placed in one vial for them to reproduce. For the di-hybrid cross, red eyed and normal winged flies and sepia eyed and vestigial winged flies were placed in their vial to reproduce. In the mono-hybrid cross the results expected were within a 1:1:1:1 ratio. Expected results similar to the expected desired null hypothesis proposed with what the F1 parental generation breeds. The potential results would have had to have been within the ratios of 9:3:3:1. The results were clear and allowed the null hypothesis to be correct. The white eyed gene in the fruit flies is sex linked. Sepia eyes and vestigial wings are not sex linked and are examples of independent assortment.
The “Fast Plant” experiment is an observation of a plants growth over the span of twenty-eight days. The objective is to observe how plants grow and use their resources throughout the span of their life. In our lab we observed the Brassica rapa, a herbaceous plant in the mustard family which has a short cycle which makes it a perfect plant to observe in this experiment. Like other plants the Brassica rapa must use the resources in the environment to create energy to complete itʻs life cycle and reproduce. By observing the plant it is easy to see in what organ or function the plant is using itʻs energy and resources and if overtime the resources switch to other part of the plants. By conducting this experiment we are able to observe where and how plants allocate their resources throughout their life by harvesting plants at different points in their life.
Introduction Within the cells of a beetroot plant, a pigment is held within the vacuole of a beetroot cell, this pigment gives the beetroot its red/purple colour. If a cell is damaged or ruptured in a beetroot and the cell surface membrane ruptures, the pigment 'drains' from the cells like a dye. It is this distinction that can be employed to test which conditions may affect the integrity of the cell surface membrane. The pigments are actually betalain pigments, named after the red beetroot (beta vulgaris) it breaks down at about 60ºC. They replace anthocyanins in plants.