Inheritance Lab Report
Inheritance Lab Report
Materials and Methods
There were no materials that were required for this lab. A variety of phenotypes were observed and recorded in the Table 1 below. Using the logic of Mendelian genetics, possible personal genotypes, as well as those of my parents were recorded. The presence of attached earlobes was recorded as yes and no if absent. For the other phenotypes, their presence was indicated by a yes and their absence with a no. The genotypes were identified based on the recorded phenotypes using the alleles indicated below.
- E – free earlobes; e – attached earlobes
- D – dimples; d – no dimples
- T – able to roll tongue; t – not able to roll tongue
- F – second toe longer than the big toe; f – second toe shorter than the big toe
- W – widow’s peak; w – no widow’s peak
All the possible pairings of parental genotypes that could have led to the recorded genotypes were also recorded for all the genotypes.
Results
The observed phenotypes and possible genotypes for my parents and I were recorded in Table 1 below.
Analysis
Mendel explained how dichotomous traits that express a given phenotype and how they are passed across generations. The inheritance involves two alleles with each parent giving out one allele (Walsh, 2013). Diferent traits appear differebtly among different indiciduals. Some of these traits include rolling od the tongue, having dimples, having a widow’s peak among others (Van Gorp, 2008). The results from the lab experiment indicate that I have free earlobe, which means that my genomes are either EE or Ee. With no dimples, the possible genotypes could be dd from either Dd X Dd or Dd X dd or dd X dd or dd X Dd parental genotypes. Presence of rolling of the tongue indicates that TT or Tt could be the possible genotypes. These genotypes could result from either TT X TT or TT X Tt or Tt X Tt or Tt X TT parental genotypes. Lack of a second toe that is longer than the big toe on the foot indicates that the possible genotype is ff, which could result from the following parental crosses Ff X ff or ff X ff or ff X Ff or Ff X Ff. Lack of a widow’s peak indicates that the present genotype is ww and may have resulted from one of the following crosses ww X ww or Ww X Ww or ww X Ww or Ww X ww.
This kind of logic may be useful predicting the genotypes of the parents when the genotype of an individual is known.
Conclusion
This analysis involved the prediction of possible genotypes of an individual using the phenotypes that are observed in an individual. The predicted genotypes were then used to predict the possible genotypes of the parents of the individual. The results indicated that several combinations of genotypes may result in production of a specific genotype. This is indicated by whether only one set of allele is possible as well as when there are two possible genotypes.
Reference List
Van Gorp, L. (2008). Gregor Mendel: Genetics Pioneer. Minnesota: Capstone.
Walsh, L. (2013). Mendelian Genetics. Retrieved February 5, 2014, from http://www.uni.edu/walsh/genetics.html
