chromosomal mutations
DESCRIPTION
Chromosomal Mutations. Karyotype. arrangement of chromosomes from one body cell. Sex Chromosomes. Determine the sex of the individual In humans: X and Y chromosomes X chromosome larger than Y chromosome. All female gametes (egg cells) contain an X chromosome - PowerPoint PPT PresentationTRANSCRIPT
Chromosomal Mutations
Karyotype• arrangement of chromosomes from one body
cell
Sex Chromosomes
• Determine the sex of the individual• In humans: X and Y chromosomes
• X chromosome larger than Y chromosome
• All female gametes (egg cells) contain an X chromosome
• Male gametes (sperm) can contain either an X or Y chromosome
• Gender of child determined by father–50% chance child will be male and 50%
female
Atypical Meiosis• Chromosomes do not separate properly
during meiosis• Results in gametes with too little or too
much genetic information
Down Syndrome• Zygote contained 47 chromosomes• 3 copies of chromosome 21
Sex Chromosome Disorders• Klinefelter syndrome:
males born with 2 X chromosomes
• Turner Syndrome: female born with only 1 X chromosome