Personal Genome Project Study Guide
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Part I: Genetic Material

Part II: Gene Transmission

Part III: Gene Expression

Part IV: Genetic Regulation

Part V: Genetics and Society

Part VI: Project Literacy






  Part II: Gene Transmission
Lesson 6: Heredity
Lesson 6 Practice Test

The diagram displays the chromosomes present in a male.  There are two of each autosomal chromosome and two different sex chromosomes.  There are two copies of every autosomal gene and one copy of each sex-linked gene.  Because one of each type of chromosome came from each parent, there are likely to be different alleles present for many of the genes on the autosomes.  The alleles may be dominant, recessive, or co-dominant.  Dominant and co-dominant alleles produce observable traits even when only one copy of the allele is present.  Recessive alleles only produce traits when no dominant alleles are also present.