Download AP Biology: Unit 3A Homework

AP Biology: Unit 3A Homework
Chapter 13 Meiosis and Sexual Life Cycles
1. Compare and contrast the following terms: asexual reproduction and sexual reproduction
2. What is the role of meiosis in sexual reproduction?
3. What is a karyotype? What can be seen with a karyotype?
4. Draw a diagram or write an explanation of the human life cycle of DNA. Include
chromosomes numbers. (pg 251)
5. Compare and contrast the following terms: mitosis and meiosis
6. Explain the following statement: “Meiosis is double division.”
7. Meiosis is an important source of variation. Define and describe how each of the following
contributes to variation within a species: independent assortment, random fertilization, crossing
over.
8. Draw a pair of homologous chromosomes and indicate a crossing over event and the products.
9. What is the signification of genetic variation and natural selection?
Chapter 14 Mendel and the Gene Idea
1. Compare and contrast the following terms: blending hypothesis and particulate hypothesis
2. What are three advantages to using garden peas as a model organism for genetic studies?
3. Define the following terms (a diagram may be used): P, F1, F2, pure, hybrid
4. What is the Law of Segregation and how does it apply to the F1 and F2 generations?
5. When does segregation of alleles occur?
6. Define the following terms: allele, gene, homozygous, heterozygous, phenotype, genotype
7. What is the purpose of a test cross?
8. When two traits are on different (non-homologous) chromosomes, how are they inherited?
9. What ratio is expected in a dihybrid cross (assume complete dominance)?
10. Use the rules of probability to determine the expected ratio of offspring showing two
recessive traits in a trihybrid cross (PpYyRr x PpYyRr).
11. Define the following terms and give an example of each: complete dominance, incomplete
dominance, codominance, multiple alleles, pleiotropy, epistasis, polygenic
12. List both the phenotype and genotype of all human blood groups and explain how they atr
examples of multiple allele inheritance.
13. Complete the following: “The expression of phenotypes is often a result of both …”
14. What is a pedigree analysis? Describe what each symbol means and how a pedigree is
constructed.
15. Briefly describe each of the following genetic disorders: cystic fibrosis, Tay-Sachs, sickle
cell anemia, achondroplasia, Huntington’s disease
16. How can a parent learn the risks of having a child with a genetic disorder?
Chapter 15 The Chromosomal Basis of Inheritance
1. What is the “Chromosomal Theory of Inheritance” and how did it come about?
2. Why was Thomas Hunt Morgan’s choice of the fruit fly a good model organism?
3. Describe Morgan’s first mutant. Why was it so significant from the wild type?
4. Show the P, F1 and F2 generations of a cross between a wild type (homozygous) female and a
white-eyed male mutant.
5. What determines sex in humans? Do all organisms share this same sex determination pattern?
6. In what ways are sex-linked traits in humans distinct from autosomal traits? How are they
passed on?
7. Why are sex-linked recessive traits more common in human males than females?
8. How many X chromosomes are typically expressed in humans and cats?
9. What happens to X chromosomes that are inactivated? How does the cell know which X
chromosome to inactivate?
10. How many Barr bodies would be found in a person with the following genotypes:
(a) XXY
(b) XO
(c) XXX
11. How are linked genes inherited?
12. Describe what genetic recombination is and how it relates to Morgan’s fly experiment.
13. Show the P, F1, and F2 generations of a cross between a homozygous gray bodied, normal
winged fly and a double mutant fly.
14. Calculate the recombination frequencies.
(a) A female dihybrid fly for body color and wing size is crossed with a male double
mutant. They have 391 recombinant offspring and 1909 non-recombinant offspring.
(b) A wild-type fruit fly (heterozygous for gray body color and normal wings) is mated
with a black fly with vestigial wings. The offspring have the following phenotypic
distributions: wild type, 778; black-vestigial, 785; black-normal, 158; gray vestigial, 162.
(c) A wild-type fruit fly (heterozygous for gray body color and red eyes) is mated with a
black fruit fly with purple eyes. The offspring are as follows: wild type, 721; blackpurple, 751; gray-purple, 49; black-red, 45.
15. Define the following terms: recombinants, crossing-over, genetic map, linkage map, map
units, nondisjunction
16. Determine the sequence of genes along a chromosome based on the following recombination
frequencies: A – B, 8 map units; A – C, 28 map units; A – D, 25 map units; B – C, 20 map units;
B – D, 33 map units.
17. Define the following terms and indicate when each occurs: aneuploidy, monosomic, trisomic,
polyploidy
18. Describe the following types of chromosomal alterations: deletion, duplication, inversion,
translocation
19. Describe the genetic basis for the following disorders: Down syndrome, Klinefelter
syndrome, Trisomy X, Turner syndrome, cri du chat
20. What is genomic imprinting? Briefly describe the Igf2 example.
21. Which organelles have genes and how are they inherited?
Chapter 16 The Molecular Basis of Inheritance
1. What are the two components of a chromosome? Which component would be the most likely
candidate for the genetic material and why?
2. Describe the experiments done by the following scientists and their conclusions:
(a) Griffith
(b) Avery
(c) Hershey and Chase
(d) Chargaff (no exact procedure given)
(e) Watson, Crick, Wilkins and Franklin
3. What is transformation?
4. If a species has 35% adenine in its DNA, what are the percents of the other three bases?
5. Describe the basic structure of DNA. Be detailed! Include base pairing.
6. What is the advantage of the double stranded aspect of DNA?
7. What are the three models of DNA replication? Describe the accepted one.
8. What happens at the DNA replication fork?
9. Make a list of the enzymes involved in replication and their roles.
10. Why does the DNA have to add nucleotides in the 5’ to 3’ direction?
11. What is the difference between the leading and lagging strands?
12. Describe the steps of DNA replication as shown in Figure 16.17, page 317.
13. What is DNA primer and why is it needed?
14. What are the steps of DNA repair and what is the advantage of DNA repair?
(a) mismatch repair
(b) nucleotide excision repair
15. What is the problem that occurs at the ends of the chromosome during replication?
16. What is a telomere and what is its role in cell division?
17. Why is there no selection pressure for prokaryotes to evolve a telomere-like solution on their
chromosome?
18. What is telomerase and why is it an active area of cancer research?
19. Describe the packaging of eukaryotic DNA.