BIOLOGY 1A Study Guide - Comprehensive Final Exam Guide - Dna, Messenger Rna, Gene
Document Summary
Inheritance patterns - question 13 on practice test. Pure breeding, curly winged, yellow bodied female crossed with pure breeding wild-type produces f1 generation of all curly winged, male yellow body, female brown body. Phenotypic difference in male and female; some kind of sex-linked inheritance pattern. Wild type is straight winged and homozygous is curly winged tells you that curly winged is dominant. X-linked dominant offspring won"t match genotypes. X-linked recessive fits model do the x and y gene pairings for this. Curly wings could be x-linked or autosomal. Methylation is one way for bacterial cells to know which dna is in it"s genome or not. A few different spots where methylation can happen and it all depends on the methylase. Methylase enzyme recognizes site on its own genome and methylates itself. Cytosine is methylated and ecori cannot recognize it. Ecori is a defense mechanism because it cuts out other dna but not itself.
