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When packaging DNA into chromosomes, place the following levels of chromosome organization in the correct order from the least compacted structure to the most compacted structure. I. Heterochromatin II. Radial loop domain III. DNA double helix IV. 30 nm fiber V. Nucleosome

Please show both sides of your scratch paper to the camera before submitting. Approximately 75% of cases of Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are caused by a deletion of a small region on chromosome 15 that contains a cluster of imprinted genes. The gene that causes PWS when deleted is normally maternally imprinted (paternally expressed) and the gene that causes AS when deleted is usually paternally imprinted (maternally expressed). If Richard inherits a chromosome 15 with the deletion from his father, what will be Richard’s phenotype?

The pedigree below shows the inheritance of a mitochondrial disorder. What is the most likely mode of inheritance for this mitochondrial disorder? Assume complete penetrance.  

Which of the following base pairings is normally found in DNA?  

The gene for nail patellar syndrome (n = normal allele; N  = mutant allele) shows linkage to the blood group A, B and O alleles (IA = blood type A; IB = blood type B; i = blood type O). The IA and IB alleles both show complete dominance over the i allele. The IA and IB alleles are co-dominant to each other. The two genes are located 20 m.u. apart. Beth has the genotype n____i   N____IA Simon has the genotype    N____i  n____IB What is the probability that they will have a normal child who is blood type B? 

Given the following sequence of genes on a chromosome, what change in chromosome structure occurred (the * indicates the centromere)? before A B C D * E F G H    after    A B C D * E F E F G H   

An individual has the sex chromosome genotype XXX. How many Barr bodies does the individual possess in each of their somatic cells? 

The gene for nail patellar syndrome (n = normal allele; N  = mutant allele) shows linkage to the blood group A, B and O alleles (IA = blood type A; IB = blood type B; i = blood type O). The IA and IB alleles both show complete dominance over the i allele. The IA and IB alleles are co-dominant to each other. The two genes are located 20 m.u. apart. An individual has the following genotype: n____i   N____ IA What is the probability that the individual will pass on a recombinant chromosome to offspring (any recombinant chromosome)? 

A mother is mildly affected with a mitochondrial disease. As she is only mildly affected, she decides to have 3 children. Her first child is also mildly affected. However, her second child is moderately affected, and her third child was severely affected and died in infancy. How can the three children display such different phenotypic variation?

What is the complement DNA strand to 5′ – GGA CGT – 3′?