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Genetic Observations Through The Studies Of Hybrid Corn, Single Gene

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Genetic Observations Through The Studies of Hybrid Corn, Single Gene Human Traits, and Fruit Flies

The basic foundation of modern genetics was led by Gregor Mendel (Corcos,
1993). Mendel was not the first to experiment with heredity, and our Lyman
Briggs biology class will not be the last to deal with genetics. Genetics is the science of heredity. In our lab, we had three main objectives. First, we evaluated our data on monohybrid and dihybrid corn cross seed counts against
Mendel’s theoretical expectations of independent assortment and the segregation of alleles. Next, we used the Hardy-Weinberg Theorem to provide a theoretically expected value for allele frequencies for single human gene traits. Lastly, …show more content…

These were a good choose because they are prolific breeders, and they only have four pairs of chromosomes (Davis, 1996). Morgan linked a fly’s eye color to its sex. He found that females carry two copies of this gene, while the male only carries one . Morgan’s work also led to a new, more wildly used way for symbolizing alleles (Campbell, 1996).

Materials and Methods

Materials and methods were as per Davis (1996). For the corn cross lab, corn was counted off of the ears of the corn, rather than through jars. For the human characteristics between 143 to 149 students were observed. Seven different single human gene traits were considered for this lab. The fruit fly cross was set up on September 24, 1996. The parental (P) generation begun with ten red-eyed males and six white-eyed females. The parent flies were removed on
October 3, 1996. Data collection was stopped on October 10, 1996.

Results

A punnett square was used for the monohybrid corn cross to find the genotypes of the potential offspring. The gamete combinations were Su=smooth seeds with an observed value of 497, and an expected value of 451.5; and su= wrinkled seeds with an observed value of 105, and an expected value of 150.5.
The chi-squared value was 18.35, this value didn’t correspond with any of the given probability values. The Null hypothesis with a 3:1 phenotypic ratio was rejected (see figure 1). Hence, the observed number of

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