Integrated Science Ch. 7

1
Integrated ScienceCh. 7

• Sex-Linked Traits

2
I. Chromosomes and the Genes They Contain

• - Chromosomes are structures in a cells nucleus
  that contain genes.
• - Genes are small sections of a chromosome that
  control our traits.
• - Genes are made of DNA.

3
A. Chromosomes

• - Humans have 46 chromosomes which contain
  around 23,000 genes.

4
B. Sex Chromosomes

• - pair of chromosomes that determine an
  individuals sex
• XX - female XY - male
• Autosomes the other chromosomes pairs except the
  sex chromosomes

5
Human Chromosomes44 Autosomes
6
Human Chromosomes 2 Sex Chromosomes
7
C. Sex-Linked Traits

• - trait controlled by a recessive allele on the
  "X" sex chromosome
• - More common in males
• - Ex. Red-green color-blindness, hemophilia

8
Can you see a number?
9
Queen Victorias Family
10
Pedigree of Europes Royal Families
11
D. Sex-Influenced Traits

• - trait controlled by an allele that is recessive
  in females and dominant in males
• - Ex. Male-pattern Baldness

12
The
End