APCH14+15REV.WKT

AP BIOLOGY: CHAPTER 14 AND CHAPTER 15 REVIEW

CHAPTER 14: MENDEL AND THE GENE IDEA:

1)Explain how Mendel’s particulate mechanism differed from the blending theory of inheritance.

2)List and explain the four components of Mendel’s hypothesis that led him to deduce the law of segregation.

3)Distinguish between the following pairs of terms: dominant and recessive;heterozygous and homozygous; genotype and phenotype.

4)Explain how a testcross can be used to determine if an individual with the dominant phenotype is heterozygous or homozygous.

5)State Mendel’s law of independent assortment and describe how this law can be explained by the behavior of chromosomes during meiosis.

6)Use the laws of probability to predict, from a trihybrid cross between two individuals that are heterozygous for all three traits, what expected proportion of the offspring would be:

  1. Homozygous dominant for the three traits
  2. Heterozygous for all three traits
  3. Homozygous recessive for two specific traits and heterozygous for the third

7)Explain why it is important that Mendel used large sample sizes in his studies.

8)Give an example of incomplete dominance and explain why it does not support the blending theory of inheritance.

9)Explain how phenotypic expression of the heterozygote differs with complete dominance, incomplete dominance, and codominance.

10)Explain why Tay-Sachs Disease is considered to be recessive at the organismal level but codominant at the molecular level.

11)Describe the inheritance of the ABO Blood System and explain why the A and B alleles are said to be codominant.

12)Define and give examples of pleiotropy and epistasis.

13)Describe how environmental conditions can influence the phenotype expression of a character. Explain what is meant by “a norm of reaction”.

14)Explain why studies of human inheritance are not as easily conducted as Mendel’s work with his peas.

15)Explain how a lethal recessive allele can be maintained in a population.

16)Describe the inheritance and expression of cystic fibrosis, Tay-Sachs Disease, and Sickle-Cell Disease (Anemia).

17)Explain why lethal dominant genes are much rarer than lethal recessive genes.

18)Explain how carrier recognition, fetal testing, and newborn screening can be used in genetic screening and counseling.

CHAPTER 15: THE CHROMOSOMAL BASIS OF INHERITANCE:

1)Explain why Drosophila melanogaster is a good experimental organism for genetic studies.

2)Explain why linked genes do not assort independently.

3)Distinguish between parental and recombinant phenotypes.

4)Explain how crossing over can unlink genes.

5)Define a map unit.

6)Explain why Mendel did not find linkage between seed color and flower color, despite the fact that these genes are on the same chromosome.

7)Explain how genetic maps are constructed for genes located far apart on a chromosome.

8)Explain what additional information cytogenetic maps can provide.

9)Describe how sex is genetically determined in humans and explain the significance of the SRY gene.

10)Distinguish between linked genes and sex-linked genes.

11)Explain why sex-linked genes are more common in human males.

12)Describe the inheritance patterns and symptoms of colorblindness, Duchenne Muscular Dystrophy, and Hemophilia.

13)Describe the process of X inactivation in female mammals. Explain how this phenomenon produces the tortoiseshell coloration in cats.

14)Explain how nondisjunction can lead to aneuploidy.

15)Define trisomy, triploidy, and polyploidy. Explain how these major chromosomal changes occur and describe possible consequences.

16)Distinguish among deletions, duplications, inversions, and translocations.

17)Describe the type of chromosomal alterations responsible for the following human disorders: Down Syndrome, Klinefelter Syndrome(XXY), Extra Y (XYY), Triple-X Syndrome, and Turner Syndrome.