the chapter 12 homework is due on sunday, january 11 at 11:59 pm the chapter 12 test will be on...
TRANSCRIPT
• The Chapter 12 Homework is due on Sunday, January 11 at 11:59 pm
• The Chapter 12 Test will be on Monday, January 12.
• The Chi-Square Quiz has been postponed until Wednesday.
• Homework for tonight: • Scientific Skills Exercise: Using the Chi-Square Test (This is part of the
Chapter 12 Homework - it will help you prepare for the lab tomorrow and the quiz on Wednesday.)
• “Notes: Chapter 12.1 Mendelian inheritance has its physical basis in the behavior of chromosomes” (I’m not going over this in class because it is just a review of information that was presented in previous chapters.)
Figure 12.4
Xw Y
Xw+
Xw+ Xw Xw+ Y
Xw+ Xw+ Xw Xw+ Y
Figure 12.4a
All offspringhad red eyes.F1
Generation
Experiment
PGeneration
XwYXw+Xw+
• A gene that is located on either sex chromosome is called a sex-linked gene.
• Genes on the Y chromosome are called Y-linked genes; there are few of these.
• Genes on the X chromosome are called X-linked genes.
• X-linked genes follow specific patterns of inheritance.
• For a recessive X-linked trait to be expressed– A female needs two copies of the allele (homozygous)– A male needs only one copy of the allele (hemizygous)
• X-linked recessive disorders are much more common in males than in females