In Drosophila, an individual female fly was observed to be of the XXY chromosome complement (normal autosomal complement) and to have white eyes as contrasted with the normal red eye color of wild type. The female's mother and father had red eyes
The mother, however, was heterozygous for the gene for white eyes. Knowing that white eyes are X-linked and recessive, present an explanation for the genetic and chromosomal constitution of the XXY, white-eyed individual. It is important that you state in which parent and at what stage the chromosomal event occurred that caused the genetic and cytogenetic abnormality.
Nondisjunction would have occurred at meiosis II in the mother, thus giving the XwXwY complement in the offspring.
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Choose the true statements about the roles of AP3 and PI in petal development in the eudicots.
_____ The C terminus sequence of the AP3 protein specifies petal development. _____ The C terminus sequence of the AP3 protein is conserved among all flowering plants. _____ AP3 has an essential role in petal development encoded at its 5' end. _____ The PI gene in eudicots retains an involvement in stamen development.
In this figure, which organ is associated with the breakdown of fat globules?
a. A b. B c. C d. D e. E
What is true about homologous structures?
a. they are always used for the same function b. they are formed from different developmental pathways c. the same genes direct their development d. they are only found within species not between species e. more than one of these is correct
What process could result from the natural selection explained by Darwin in his book The Origin of Species?
What will be an ideal response?