Inheritance of Sex

• How many pairs of chromosomes do humans have?

  23 pairs
• What do 22 of the chromosome pairs contain?

  Genes determining inherited characteristics
• What are the sex chromosomes in males?

  X Y
• What are the sex chromosomes in females?

  X X
• What is the significance of the sex chromosomes being different in males?

  It indicates the male sex
• What do all of the woman's gametes contain?

  X chromosome
• What do half of the man's gametes contain?

  X and Y chromosomes
• If a couple has offspring, what are the possible combinations of sex chromosomes?

  XX or XY
• What percentage of the offspring are expected to be female?

  50%
• What is the expected ratio of male to female offspring?

  1 to 1
• What does the actual outcome of offspring sex depend on?

  Probabilities
• What might happen in reality regarding the sex of offspring?

  All could be male or all could be female
• Where can you find questions on the inheritance of sex?

  In the revision workbook
• What is the purpose of the video?

  To describe the inheritance of sex