Chapter 12The Chromosomal Basis of Inheritance

Key Concepts

Morgan showed that Mendelian inheritance has its physical basis in the behavior of chromosomes
Sex-linked genes exhibit unique patterns of inheritance
Linked genes tend to be inherited together because they are located near each other on the same chromosome
Alterations of chromosome number or structure cause some genetic disorders

Detailed Learning objectives

12.1 Describe why sex-linked disorders are much more common in males than in females (color-blindness in humans)

12.2 Perform a sex-linked genetic cross

12.3 Describe how recombinant and non-recombinant (parental) chromosomes are formed (crossing over between linked genes versus no crossing over)

12.4 Describe nondisjunction

12.5 Compare and contrast aneuploidy (i.e. monosomic and trisomic) versus polyploidy (i.e. triploidy and tetraploidy)

Lecture Slides

Chapter 12 Lecture Slides

assignments

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Terminology

Key Terminology and Vocabulary - While the "jargon" or terminology in scientific fields can initially be intimidating, the use of specific language allows for more effective communication and clarity. Learn these words and be able to use them properly in the context of biology. It takes time and practice to make words "your own" so don't be afraid to try to use them!

chromosome theory of inheritance
wild type
sex-linked gene/X-linked gene
Human X-linked conditions
- Duchenne muscular dystrophy
- Hemophilia
Barr body
linked genes
genetic recombination
parental types vs. recombinant types
crossing over
genetic map
linkage map
- map units
Nondisjunction
- aneuploidy
  - monosomy
  - trisomy
Polyploidy
Chromosome mutations
- deletion
- duplication
- inversion
- translocation
Down syndrome