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6.  Examine the human karyotype below and answer the associated questions.        a.  Does this karyotype indicate a male or a female human?  How do you know?      b.  Name the syndrome associated with the non-disjunction aneuploidy shown in the karyotype.      c.  Which one of the following correctly describes the “source” of this aneuploidy:                Non-disjunction that could only have occurred during oogenesis.                Non-disjunction that could only have occurred during spermatogenesis.                Non-disjunction that could have occurred during oogenesis or occurred during spermatogenesis.

1.  Which one of the following choices correctly diagrams the Central Dogma of Biology?

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17.  Identify each chromosomal designation as indicative of aneuploidy, polyploid, or neither aneuploidy or polyploidy.  The chromosomal designations all apply to the chromosomal complement of human cells.

18.  The diagram below shows spermatogenesis (on the left) and oogenesis (on the right) followed by a fertilization event.  The numbered circles are cells.  The long purple bars in the cells are X chromosomes while the short blue bars in the cells are Y chromosomes.  Cell #8 is the zygote resulting from fertilization.          a.  Where has the non-disjunction occurred?  Use the number to the upper left of the cell to help you explain the location of the non-disjunction.       b.  What non-disjunction syndrome does this illustration demonstrate?  How do you know?

13.  The roseatte spoonbill is a bird that lives in mangrove marshes and captures insects with a long spoon-shaped bill.  Bill color is due to a gene that has two incompletely dominant alleles.  Individuals that are homozygous for one allele have a black bill.  Individuals that are homozygous for the other allele have a bill that is almost white. What color bill will heterozygous individuals most likely express?  Explain the reasoning/rationale behind your answer.

7.  Which one of the following correctly describes the activity of the Xist gene responsible for X-inactivation?

4.  Which of the following are assumptions of Mendelian genetics?  Select all correct choices.

5.  Match the allele combination with the correct term used to describe that genotype combination.

16.  The illustration below shows a chromosome on which the loci (locations) of 4 linked alleles (a, B, C, and d) have been mapped.   Which two alleles are least likely to be “unlinked” during crossing over?  Why did you pick these two alleles?