Sex Linkage Inheritance


×
Rating : Rate It:
 
 
chikki    on Nov 24, 2011 Says :

hai darlig
chikki    on Nov 24, 2011 Says :

hai
Post a comment
    Post Comment on Twitter
Comments:  



  Notes
 
 
1 : Inheritance Sex Linkage
2 : What is Sex Linkage? In addition to their role in determining sex, the sex chromosomes have genes for many characters. Genes located on a sex chromosome are called sex linked genes. In humans the term usually refers to X-linked characters: genes located only on X chromosomes. Fathers can pass X-linked alleles to their daughters, but not sons. Mothers can pass sex-linked alleles to both sons and daughters.
3 : Recessive alleles If a sex linked trait is due to a recessive allele: A female will express the phenotype only if she is homozygous recessive. If a male receives the recessive allele from his mother he will express the phenotype. Far more males have disorders that are inherited as sex linked recessives than females. Examples: Colour blindness Haemophilia
4 : Red-green colour blindness X chromosome has a locus for colour vision with two alleles: XN = Normal colour vision Xn = Red-green colour blindness Y chromosome does not have a colour vision locus. If a male receives the Xn allele he will have impaired colour vision, whereas a female with XNXn will not.
5 : Red-green colour blindness Parental Phenotypes Carrier Female x Normal Male Genotypes XNXn XNY Gametes Offspring 1 Genotypes Phenotypes Normal Female : Carrier Female : Normal Male : Colour blind Male 1 : 1 : 1 : 1 XN Xn XN Y
6 : Showing genetic pedigree Unaffected female: Affected female: Unaffected male: Affected male: 1 2 1 2 3 4 5 1 2 3 4 5 I II III
7 : What now? Complete WS5: Sex-Linked Genes Complete WS6: Extension questions
8 : This powerpoint was kindly donated to www.worldofteaching.com http://www.worldofteaching.com is home to over a thousand powerpoints submitted by teachers. This is a completely free site and requires no registration. Please visit and I hope it will help in your teaching.

 

Add as Friend By :
Added On : 4 Years ago.
In addition to their role in determining sex, the sex chromosomes have genes for many characters.Fa    more
Views 5894 | Favourite 0 | Total Upload :628022

Embed Code:

Flag as inappropriate


Related  Most Viewed



Free Powerpoint Templates

 



Free Medical PowerPoint Templates | Powerpoint Templates | Tags | Contact | About Us | Privacy | FAQ | Blog

© Slideworld