Show simple item record

dc.contributor.authorHaj-Ahmad, Yousef.en_US
dc.date.accessioned2009-10-02T13:20:00Z
dc.date.available2009-10-02T13:20:00Z
dc.date.issued1981-10-02T13:20:00Z
dc.identifier.urihttp://hdl.handle.net/10464/2749
dc.description.abstractA. strain of Drosophila melanog-aster deficient in null amylase activity (Amylase ) was isolated from a wild null population of flies. The survivorship of Amylase homozygous flies is very low when the principal dietary carbohydrate source is starch. However, the survivorship of the null Amylase genotype is comparable to the wild type when the dietary starch is replaced by glucose. In addition, the null viability of the amylase-producing and Amylase strains is comparable v and very lm<] f on a medium with no carbohydrates . Furthermore, amylase-producing genotypes were shovm to excrete enzymatically active amylase protein into the food medium. The excreted amylase causes the external breakdown of dietary starch to sugar. These results led to the following null prediction: the viability of the A.mvlase genotype (fed on a starch rich diet) might increase in the presence of individuals which were amylase-producing. It was shown experimentally that such an increase in viability did in fact occur and that this increase v\Tas proportional to the number of mnylase..::producing fli.es present. These results provide a unique example of a non-"competi ti ve inter-genotype interaction, and one where the underlying physio~ logical and biochemical mechanism has been fully understood.en_US
dc.language.isoengen_US
dc.publisherBrock Universityen_US
dc.subjectDrosophila melanogaster.en_US
dc.subjectAmylases--Analysis.en_US
dc.subjectNatural selection.en_US
dc.subjectPopulation genetics.en_US
dc.titleFrequency-dependent selection at the amylase locus in Drosophila melanogasteren_US
dc.typeElectronic Thesis or Dissertationen_US
dc.degree.nameM.Sc. Biological Sciencesen_US
dc.degree.levelMastersen_US
dc.contributor.departmentDepartment of Biological Sciencesen_US
dc.degree.disciplineFaculty of Mathematics and Scienceen_US


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record