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Health & Human Development
Hormones and puberty
Hormones play an important role in controlling or regulating many processes in the body, including physical
development during youth. They are often referred to as ‘chemical messengers’ because they circulate in the
bloodstream and act on various sites in the body, stimulating a particular process. Hormones regulate metabolism,
growth, development and reproduction.
Hormones are manufactured and released directly into the bloodstream from glands called endocrine glands. They
include:
• the thyroid gland (in the neck)
• the adrenal gland (near the kidney)
• the pituitary gland (at the base of the brain)
• the testes and the ovaries.
The pituitary gland is often called the ‘master gland’ because it controls the actions of other endocrine glands by
stimulating them to release their hormones. The pituitary gland is in turn regulated by an area of the brain called
the hypothalamus. The hypothalamus detects messages from the nervous system as well as hormone levels in the
blood. It is then able to respond by promoting or inhibiting the secretion of hormones from the pituitary gland.
Puberty begins when the hypothalamus stimulates the pituitary gland to secrete two hormones, follicle stimulating
hormone (FSH) and luteinising hormone. These hormones stimulate the ovaries and the testes to increase
production of the sex hormones—oestrogen (female) and testosterone (male).
Pituitary Gland secretes
 Growth hormone (GH)
 Thyroid stimulating hormone (TSH)
 Adrenocortictrophic hormone (ACTH)
 Luteinizing hormone (LH)
 Follicle stimulating hormone (FSH)
GROWTH HORMONE (GH)
 Stimulates growth spurt
 Acts on all cells except central nervous system
 Affected by nutritional status, emotional disturbance, deprivation of love and affection (failure to
thrive)
THYROID STIMULATING HORMONE (TSH)
 Operates with iodine
 Causes release of energy from food
 Effects circulatory, nervous, reproduction, digestion, renal
 Controls rate of growth
 Feedback system maintains constant hormone level
FOLLICLE STIMULATING HORMONE (FSH)
 Only released prior to puberty and stimulates follicles in girls to secrete oestrogen
OESTROGEN (FEMALE)
 Growth breasts
 Adult shape
 Growth reproductive organs
 Regulation of menstrual cycle with progesterone
TESTOSTERONE (MALE)
 Deep voice
 Facial hair
 Male body shape
 Pubic hair
 Growth male sex organs
LUTEINIZING HORMONE (LH)
 Ovulation in females
 Secrete testosterone in males
ADRENOCORTICTROPHIC HORMONE (ACTH)
 Effect on sexual maturation
 Provides energy for growth spurt
Hormones & Puberty
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