Write notes on - (a) Adam's apple: (b)Secondary sexual characters in girls: (c) Sex determination in an unborn baby:

(a) Adam's apple:

1. It is a protruding part of the throat present in boys.
2. It is visible from the outside as the voice box and larynx enlarged at the onset of puberty.
3. It makes boys' voices hoarse.

(b) Secondary sexual character in girls:

1. It is a physical and behavioral characteristic appearance in girls at the time of puberty.
2. In girls it includes:

• Increase in breast size.
• growth of hip muscle and pelvic girdle.
• growth of hair in the genital area and armpit.

(c) Sex determination in unborn baby:

1. The sex of an unborn baby depends on the sex chromosomes X and Y exhibited by the cells of the baby.
2. Unfertilized eggs always have one chromosome.
3. Sperm have two kinds of X and Y chromosomes while the ovum has the only copy of the X chromosome.
4. On fertilization, if both chromosomes are X then the baby will be a girl whereas if one chromosome is Y and the other is X then the baby will be a boy.
5. In India, the sex determination of an unborn baby is a punishable offense.