Bio questions

1. What is genetics? Who is considered to be the “Father of genetics”?
2. What type of organism did Mendel use to form his ideas about inheritance? Why was this organism ideal to use for Mendel’s genetics experiments?
3. What are true-­?breeding varieties? Describe thecross that Mendel performed between two true-­breeding plants for flower color (purple and white). What three hypotheses did Mendel develop from the results of this experiment? What law did Mendel develop based on these crosses?
4. What are Punnett squares, and why are they used?
5. When you look at yourself in the mirror, are you observing your genotype or phenotype?
6. We usually name genes as the first letter of the dominant allele. Mendel’s pea plants can have yellow
or green seed color alleles and yellow is the dominant allele. What letter would we use to represent the
gene that codes for seed color? If a pea plant has a gene on one homolog that codes for yellow and a
gene on the other homolog that codes for green, what is the genotype of the plant? What is the
phenotype? Would we consider this plant to be homozygous or heterozygous for the seed color gene? What color are the seeds on this plant?
7. What would be the expected genotypic and phenotypic ratios of offspring in a cross between a pea plant homozygous for tall height with a heterozygous pea plant? Show your work in a Punnett square.
8. Describe Mendel’s Law of Independent assortment.
9. In pea plants there are two versions (alleles) of the flower color gene: P = purple flowers, and p = white flowers. There are also two versions of the height gene: T = tall plant, and t = short plant. Use a Punnett square to determine the phenotypic ratios of the following crosses:
a. PPTt x PpTt
b. PpTt x PpTt
10. What is a test cross, and when is a test cross useful?
11. What is a pedigree?
12. Brown eye color is dominant over blue eye color. A brown-­?eyed woman whose father has blue eyes and whose mother has brown eyes marries a brown-­?eyed man whose parents are also brown-­?eyed. The woman and man have a son who is blue-­?eyed. Please draw a pedigree showing all four grandparents, the two parents and the son. Indicate the individuals for which you are certain of their genotype and the individuals for which there is more than one possibility.
13. How does incomplete dominance differ from complete dominance? Give a real life example of incomplete dominance.14. Red is incompletely dominant over white for the color of snapdragon petals. Starting with true­?bred parents, one with red petals and one with white petals, show the phenotypic ratios for the F 1 and F2 generations.
15. What are multiple alleles? Give a real life example.
16. How does codominance differ from complete dominance? Give a real life example of codominance.
17. A mother has blood type A and genotype I A i. A father has blood type B and genotype I B i. What are the possible blood types of the offspring?
18. What is pleiotropy? Give a real life example.
19. What are polygenic traits? Give a real life example.
20. Can the environment play a role in the phenotypic expression of the genes? If so, give a real life example.
21. What are linked genes? How do linked genes relate to the law of independent assortment? What can break up the linkage between linked genes?22. What are sex-­?linked genes? What are some examples of sex-­?linked disorders in humans? Why are males more likely than females to express sex-­?linked disorders?23. A heterozygous woman with normal color vision has a child with a colorblind man. How many, if any, of the children will also be colorblind? How many of the affected (colorblind) children are girls and how many are boys?