Hormones & Puberty (DP IB Biology: HL): Revision Note

Hormones & Puberty

• During puberty, reproductive hormones cause secondary sexual characteristics to develop

• This is under the control of hormones, two types of sex hormones include

  • Gonadotropin-releasing hormone (GnRH) 

  • Steroid sex hormones such as oestrogen (also known as oestradiol) and testosterone

• The increase in sex hormones production leads to the changes associated with puberty

  • The onset of puberty is triggered by the release of hormones from the hypothalamus in the brain which secretes GnRH

  • This is detected by the pituitary gland (situated underneath the hypothalamus) which in turn secretes two further hormones

    • LH

    • FSH

  • These hormones are produced in both females and males and they enhance the effects of the sex hormones oestrogen and testosterone

  • Following this the development of the secondary sexual characteristics takes place

Male secondary sexual characteristics

The development of male secondary sexual characteristics at puberty are under hormonal control

Female secondary sexual characteristics

The development of female secondary sexual characteristics at puberty are under hormonal control