endocrine system

• endocrine glands


  produce and secrete hormones that regulate the activity of cells or organs in the body.
• A signal is sent from the hypothalamus to the pituitary gland to release a stimulating hormone into the bloodstream. This stimulating hormone then signals the target gland to secrete the hormone. As this level of hormone increases in the bloodstream, the hypothalamus shuts

  down secretion of the stimulating hormone. This slows down secretion of the target glands hormone, resulting in stable concentrations of hormones circulating in the bloodstream.
• pituitary gland - located in the brain


  -'master gland' - controlled by hypothalamus

  -influences release of hormones from other glands and regulates functioning of them

  -produces hormones that travel in bloodstream to their target, these hormones ca cause changes in body or stimulate other glands to produce hormones

  High levels of hormones produced in other endocrine glands can

  stop the hypothalamus and pituitary releasing more of their own hormone. This is called

  negative feedback and prevents hormone levels from rising too high.
• adrenal glands - just above kidneys


  -produces adrenaline and cortisol

  adrenaline- prepare the body to deal with stressors. To do this it provides the body with a burst of energy, increases heart-

  rate, respiration and dilates pupils.

  Cortisol- help the body deal with stressors. It has anti-inflammatory functions, increases our blood sugar and decreases sensitivity to pain.
• testes ,,,,,,
• ovaries......dwedewe fe
• endocrine system definition


  network of cells that communicate by releasing hormones into the bloodstream