Inheritance of Sex

• How many pairs of chromosomes do humans have?

  23 pairs
• What is the purpose of the video titled "three sighs lessons cold UK"?

  To describe the inheritance of sex
• What do the 22 pairs of chromosomes in humans contain?

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

  X and Y
• What are the sex chromosomes in females?

  X and X
• How do the gametes produced by a female differ from those produced by a male in terms of sex chromosomes?

  All female gametes have the X chromosome, while male gametes have both X and Y chromosomes
• If a couple has a male offspring, what combination of sex chromosomes did the offspring inherit?

  One X chromosome and one Y chromosome
• What is the expected ratio of male to female offspring in human reproduction?

  • 50% female (XX)
  • 50% male (XY)
  • Ratio of 1:1
• Why is it important to remember that the sex chromosome inheritance is based on probabilities?

  Because a couple might have several offspring that could all be male or all be female
• Where can students find questions on the inheritance of sex for revision?

  In the revision workbook linked in the video