Human Growth and Development / Unit 9 HGD 1221 worked example, 60 to 90 seconds
The HPG Axis
The idea
Pubertal hormones run through the hypothalamic-pituitary-gonadal axis, known as the HPG axis. The hypothalamus releases gonadotropin-releasing hormone, GnRH. That signals the pituitary gland to secrete follicle-stimulating hormone, FSH, and luteinizing hormone, LH. These act on the gonads, the testes and ovaries, which produce the sex hormones that drive the changes of puberty.
In practice
A chain of signals: hypothalamus to pituitary to gonads, each step triggering the next, over months and years.
Where people slip
The HPG axis is often confused with the HPA axis, hypothalamic-pituitary-adrenal, which is the body's stress axis. The two share their first two links and differ at the end: gonads for puberty, adrenal glands for stress. For the exam, know the order of the chain and the hormones at each step.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
Unlocks
- Nothing yet depends on this.
Something wrong in this lesson? Flag it · Sources for Human Growth and Development