Lesson 07 ­ Sex­Linked Inheritance.notebook
Sex­Linked Inheritance
Video - Colour blindness test
Video - Sex-Linked traits
INTRODUCTION
When Mendel formed his Law of Inheritance, he had no idea about the existence of ______________ or ______________________. We know that traits are located on chromosomes, and some are located on the X and Y chromosome, which means the inheritance of some traits depends on the ____________ of the parent carrying the trait. X vs. Y CHROMOSOME
Most known sex­linked traits are ______________ (carried on the X chromosome). This is likely because the X chromosome is much _____________ than the Y chromosome.
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Lesson 07 ­ Sex­Linked Inheritance.notebook
SEX­LINKED DISORDERS
Some sex­linked traits are associated with disorders. Most are found on the ____ chromosome, and ______­linked disorders are rare.
Males are at a much greater risk for inheriting sex­disorders because they only inherit ______________________________, so if the X has the allele for the disorder, they will suffer from the disorder. Male pattern _______________________, red­green ________ ___________, myopia, night blindness, and __________________________ are examples of sex­linked disorders.
EXAMPLE PROBLEM
Hemophilia is a recessive X­linked trait. What is the probability of a couple having a hemophiliac child if the man does not have hemophilia and the woman is a carrier?
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