Bio 12 Genetics
Using ppt on Principles of Heredity, answer the following questions:
1. What is a purebred?
2. Define the term genetics.
3. What were the dominant believes about heredity until the 20’Th century?
4. How did Mendel cross-fertilize the plants in his experiments?
5. What is a phenotype and what were the phenotypes studied by Mendel?
6. How many alleles does an organism have for each inherited characteristic?
7. When do pairs of alleles separate? What is the law of segregation?
8. What is the difference between a dominant and recessive allele?
9. What is a gene loci?
10. What is the principle of independent assortment?
11. Make a Punnet square for the cross between parents with GG Gg. Which is
dominant? How do you know?
12. To illustrate independent assortment with a punnent square, show how the
following genotype would be represented in the F2 generation: GGYY x ggyy
13. What mathematical rule do Mendel’s principles follow?
14. What is a Pedigree?
15. What is an autosomal recessive allele?
16. What kind of alleles most often cause inherited disorders?
17. Give 2 examples each of recessive disorders and dominant disorders.
18. What is karyo-typing and describe two ways this can be done to a human fetus.
19. Explain incomplete dominance.
20. Give an example of a characteristic dependent upon multiple alleles.
21. What is pleiotropy? Polygenic inheritance?
22. What is a linked gene?
23. How are new combinations of genes produced?
24. How do geneticists map genes?
25. Name 4 ways that sex determination occurs in animals?
26. Why do males more commonly have sex-linked disorders?
27. When will a recessive trait be visible in an organism's phenotype?
Bio 12 Genetics
28. One cat carries heterozygous, long-haired traits (Ss), and its mate carries
homozygous short-haired traits (ss). Use a Punnett square to determine the
genotypes and phenotypes of the offspring.
29. One flower is heterozygous red (Rr) and it is crossed with a homozygous white
(rr) plant. Use a Punnett square to determine the probability of one of their
offspring having a red color.
30. In a certain species of plant, the color purple (P) is dominant to the color white
(p). According to the Punnett Square, what is the probability of an offspring
being white?
31.
If two people who are both carriers for a genetically inherited fatal recessive
disease decide to become parents, what will be the odds that their children will
also be carriers?
32. If a woman is homozygous normal and her husband is heterozygous for a
genetically inherited recessive disease and they decide to become parents, what
is the probability that they will have a healthy child?
33. If two parents are heterozygous for a genetically inherited dominant trait, what
is the probability that they will have a child together who has this trait in his or
her phenotype?
34. Black fur (B) in guinea pigs is dominant over white fur (b). Find the probability
of a white offspring in a cross: Bb x bb.