Download Biology Homework Chapter 8

Biology Homework Chapter 8: Heredity and Genetic Variation
Answer the questions with complete thoughts and complete sentences!
* Sections 8.1 and 8.3: The hereditary Role of Genetic material. Read pages 183 to 188
PART A: Using index cards, put the term on the front and its definition on the backside.
Row 1
DNA
HEREDITY
GENE
CHROMOSOME
Row 2
TRAIT
PROBABILITY
NUCLEOTIDE
BASES
P1
(parental generation)
Row 3
F1
(1st Filial)
F2
(2nd Filial)
DOMINANT
TRAIT
RECESSIVE
TRAIT
Row 4
ALLELES
PRINCIPLE OF
SEGREGATION
GENOTYPE
PHENOTYPE
Row 5
HOMOZYGOUS
HETEROZYGOUS MONOHYBRID
CROSS
HOMOLOGOUS
CHROMOSOMES
PART B:
1. Who was Gregor Mendel and what was the importance of his work? Provide specific details
about why he chose to work with pea plants, how his experiment was unique and well designed, and
what he discovered.
2. If you were going to check and see if you had true breeding plants, what type of pollination
would you want to occur and why?
Page 1 of 7
PART C:
Read, study and know pages 183 - 188.
1. What are the chances that a family with 3 children will have three daughters? After a family has
2 daughters, what is the probability that their next child will be a daughter?
2. How was mathematics important in Mendel’s explanation of his results?
3. Distinguish between the terms gene and allele.
4. Distinguish between genotype and phenotype; between homozygous and heterozygous.
5. Explain how the principle of segregation applies to the movement of chromosomes in meiosis.
******************************************************************************
* Sections 8.4 and 8.7: Patterns of Inheritance. Read pages 188 - 195
PART A: Using index cards, put the term on the front and its definition on the backside.
Row 1
Row 2
DIHYBRID
CROSS
AUTOSOMES
PRINCIPLE OF
INDEPENDENT
ASSORTMENT
X-LINKED TRAITS
aka. Sex linked traits
Page 2 of 7
CODOMINANCE
MULTIPLE
ALLELES
TRISOMY
NONDISJUNCTION
PART B:
1. What is a karyotype and what type of information can it help a genetic counselor determine?
2. Who was Thomas Hunt Morgan and in general what was the importance of his work?
3. Draw and Explain how non-disjunction during meiosis can result in an individual having an
extra chromosome (47 of them!). Please refer to either Trisomy 21 or Klinefelter’s Syndrome (XXY)
in your explanation. (See figure 8.14, page 194 for help)
PART C:
Read, study, and know pages 188 - 195.
1. How does the movement of chromosomes during meiosis explain the principle of independent
assortment?
2. How does codominance account for the presence of more than two phenotypes of a trait?
3. What are multiple alleles? Can a person have more than 2 alleles for a single gene? Explain.
Page 3 of 7
4. Describe how multifactorial inheritance explains continuous variation in a trait such as height.
5. How can karyotypes contribute to genetic research?
6. How does the inheritance of X-linked traits differ from that of other traits?
7. Why are the effects of genotypes with extra X chromosomes apparently less severe than those of
other trisomies?
Essay:
1. Explain the difference between Mendel’s two laws: The Law of Segregation and the Law of
Independent Assortment (i.e., What do each of them conclude about heredity?).
Page 4 of 7
* Sections 8.8 and 8.10: Genes and Chromosomes. Read pages 196 - 199
PART A: Using index cards, put the term on the front and its definition on the backside.
Drosophila melanogaster
Crossing over
Gene Linkage
PART B:
1. What is the significance of the work of Alfred Hershey and Martha Chase in biology?
2. What did Watson and Crick hypothesize about the structure of DNA? What are the 3 properties
of genes that are explained by their molecular model of DNA?
PART C:
Read, study and know pages 196 - 199.
1. Why would the knowledge that genes are made of DNA rather than protein be helpful to
biochemists trying to isolate and study genes?
2. Sketch and describe the structure of the DNA molecule.
Page 5 of 7
3. Describe the evidence for the chromosome theory of heredity.
4. How does crossing over affect gene linkage?
5. Describe how linkage can be used to prepare chromosome maps.
******************************************************************************
* Sections 8.11 and 8.12: Gene Expression. Read pages 199 - 203
PART A: Using index cards, put the term on the front and its definition on the backside.
Row 1
Row 2
Beadle & Tatum
tRNA
Protein synthesis
rRNA
PART B:
1. Define DNA replication.
2. Where in the cell does DNA replication take place?
3. Define transcription.
Page 6 of 7
mRNA
Codon
4. Where in the cell does transcription take place?
5. Define translation.
6. Where in the cell does translation take place?
7. What molecules and structures are involved in synthesizing a protein?
8. What two processes or steps are involved in protein synthesis?
9. Where in the cell does protein synthesis take place?
PART C:
Read, study and know pages 199 - 203.
1. What did the x-rays in Beadle and Tatum’s work produce in their mold specimens? What
happened as a result? Which trait was dominant and which was recessive?
2. Is the mRNA strand an exact copy of the DNA strand from which it is synthesized? Explain
your answer.
3. How is the genetic information coded in DNA translated into protein?
Page 7 of 7