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Week 8 : Inheritance

To-Do Date: Mar 6 at 12:00pm

Cartoon

In this cartoon, the speakers announce that they have discovered the ''Gullibility Gene'' and they need the audience members to donate ipads, cookies, and opportunities on a TV show.  Explain why it is unlikely that there is a single gene that codes for gullibility, 

2010-04-19-gullibility.jpg

 

Learning Objectives 

By the end of these modules, students should be able to 

    • Given the right information, you should be able to figure out the patterns of inheritance for a particular gene. Specifically, at the end of today’s lab you should be able to:
    • Determine whether a gene has a simple dominant and recessive system.
    • Determine which allele is dominant and which recessive.
    • Given the genotype of parents, determine the genotype and phenotype of the offspring.
    • Calculate expected ratios of different phenotypes in offspring.
    • Know the genetics vocabulary terms.
    • Determine genetics problems with partial dominance (incomplete dominance and co–dominance., multiple alleles, and x–linkage).
    • Figure out the genotype of parents or offspring, if given enough information about phenotype.
    • explain the idea of gene expression and predict which genes will be expressed in different types of cells. 
Gene Heterozygous Genotype Partial dominance 
Allele Dominant  Phenotype  Multi-gene trait 
Homozygous (true breeding recessive  X-linked 

Study Guide Questions

1. When we follow patterns of inheritance, we assume that each parent gives only one copy of a gene to their offspring, who then end up having 2 copies per gene ( one from each parent). Explain why this is the case, using your knowledge of meiosis, fertilization and homologous chromosomes. 

2. Explain why  alleles for the same gene result in different phenotypes. Use your knowledge of genes, proteins, and gene expression to answer this question.

3. How can you tell the difference between a trait that is controlled by a) simple dominance/recessive alleles  b) incomplete dominance c) sex linkage or d) more than one gene. For each of these types of inheritance, give an example

4. Gene expression. For each cell record whether you expect it to have each gene in its DNA/chromosomes? (yes or no) And do you think that gene is expressed? ( yes or no)

 

Gene

 White Blood Cell Pancreatic Cell  Nerve Cell 
Gene for enzymes of glycolysis

Present- yes or no

Expressed- yes or no

Present- yes or no

Expressed- yes or no

Present- yes or no

Expressed- yes or no
Gene for an antibody

Present- yes or no

Expressed- yes or no

Present- yes or no

Expressed- yes or no

Present- yes or no

Expressed- yes or no
Gene for Insulin 

Present- yes or no

Expressed- yes or no

Present- yes or no

Expressed- yes or no

Present- yes or no

Expressed- yes or no

 

3. Be able to do the genetics problems in the lab textbook on incomplete dominance, multiple alleles, sex linkage 

 

 

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