1. Consider 3 pairs of homologous chromosomes with centromeres labeled A1/A2, B1/B2, and C1/C2 where the slash line separates one chromosome from its homologue. a). How many different kinds of meiotic products can this individual produce? b). Develop a general formula that expresses the number of different types of gametic chromosomal combinations which can be formed in an organism with k pairs of chromosomes.

2. When a plant of chromosomal type aa pollinates a plant of type AA, what chromosomal type of embryo and endosperm is expected in the resulting seeds?

3. At what stage in the cell cycle does chromosome replication occur? At what stage does chromosome replication occur in meiosis?

4. Three markers are being mapped. The observed recombination frequencies are: d-e, 4.0%; e-f, 2.5%; and d-f, 1.5%. What is the genetic map for these markers?

5. What is the relationship between the amount of DNA in a somatic cell and in a gamete?

6. In what direction do DNA and RNA polymerases move along a template strand?

7. In gel electrophoresis do smaller double-stranded molecules move more slowly or more rapidly than larger molecules? Towards which pole does the DNA migrate (i.e., positive or negative)?

8. How do exonucleases and endonucleases differ?

9. Name the bases in DNA. Which of them form base pairs?

10. What is meant by maternal inheritance?

11. At one time the possibility was considered that the genetic code might be an overlapping code of the following type: the condons in base sequence CATCATCAT...would be CAT ATC TCA CAT.... How was this hypothesis affected by the observation that mutant proteins usually differ from wildtype protein by a single amino acid?

12. Will a change in the first base of a codon necessarily produce a nonfunctional protein?

13. If you knew the base sequence of a wildtype and a mutant, would you know anything about the dominance or recessiveness of the mutation?

14. What term describes a gene that is expressed continually, even though its transcription may be auto-regulated?

15. What is the advantage of using a plasmid with two antibiotic-resistance genes as a cloning vehicle?

16. Give two reasons why a cloned prokaryotic gene might not be expressed in a prokaryote.

17. Summer squash can be found in three shapes: disk, spherical, and elongate. In one experiment, two squash plants with disk-shaped fruits were crossed. The first 160 seeds planted from this cross produced plants with fruit shapes as follows: 89 disk, 61 sphere, and 10 elongate. What is the mode of inheritance of fruit shape in summer squash?

18. Mendel crossed tall pea plants with dwarf ones. The F1 plants were all tall. When these F1 plants were selfed to produce the F2 generation, he got a 3:1 tall to dwarf ratio of offspring. Give the genotypes and phenotypes and relative proportions of the F3 generation produced when the F2 generation was selfed.

19. In one sentence or two, state Mendel's two "laws."

20. What are Southerns, Northerns and Westerns?
    

21. What is transposon-tagging?
    

22. What is insertional mutagenesis?
    

23. What is "RFLP" an acronym for?
    

24. Name at least five factors lead to deviations from Mendel's laws.
    

25. In pea plants, tall growth habit (Le) is dominant to dwarf (le), tendrils (Tl) is dominant to tendrilless (tl), and round cotyledons (R) is dominant to wrinkled (r). A homozygous wildtype inbreed plant is crossed with a dwarf, tendrilless, wrinkled-seed variety. What types of gametes will be produced by the resulting F1 plants, and in what relative proportions a) assuming independent segregation or b) assuming tight linkage between Tl and R?
    

26. A true-breeding wildtype Arabidopsis thaliana plant (Ap1/Ap1)was crossed to the flowering mutant apetala1(ap1/ap1). Sixteen F2 seed were planted, and the first twelve were wildtypes (Ap1/-). What is the probability that the remaining four plants will be the mutant (ap1/ap1)?
    

27. Name two differences between RNA and DNA.
    

Problems 3-16 from Hartl, D L, Freifelder, D and L A Snyder. (1988) Basic Genetics. Jones and Bartlett, Publishers. pp 505.

Problems 17 and 18 from Tamarin, Robert H. (1996) Principles of Genetics, fifth edition. Wm. C. Brown Publishers, E. M Sievers, Ed. Pp 683.

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