Hormones

• Water Soluble Hormones

  cannot cross the lipid membrane and interact with cells by binding to external receptor cites
• Fat Soluble Hormones

  can diffuse across the lipid membrane and interact with cells by binding to receptor cites
• hGH

  secreted by the anterior pituitary, increases protein synthesis, cell division and growth
• Hyposecretion

  dwarfism
• Hypersecretion

  gigantism
• Thyroxine


  secreted by the thyroid gland, stimulated by tropic hormones, increase rate of metabolism, requires iodine to produce
• Insufficient Iodine

  inhibits thyroxine production, meaning there will be no signal to stop TSH
• Graves Disease


  decrease of thyroxine, weight loss and decrease of energy
• Goitre


  caused by a deficiency of thyroxine and an over stimulation on the thyroid gland
• Calcitonin


  secreted by the thyroid, stimulates uptake of calcium into bones, lowering blood calcium levels
• Parathyroid Hormone (PTH)


  secreted by the parathyroid, raises blood calcium levels when low concentration
• Epinephrine


  short-term response to stress, neurons from the hypothalamus send signals to the adrenal medulla to secrete epinephrine
• Cortisol


  produced by the adrenal cortex, stimulated by ACTH, increases energy available to cells by promoting the breakdown of fats, proteins and glucose
• Aldosterone


  produced by the adrenal cortex, increases blood pressure by increasing sodium absorption into the bloodstream
• Addison's Disease


  damage to the adrenal cortex, limited aldosterone and cortisol
• What are the Symptoms of Addison's Disease?

  low blood sugar, low blood pressure, ion imbalance and weight loss
• Insulin


  recreated by beta cells, decreases blood glucose levels, temporary storage of glucose as glycogen
• Glycagon


  recreated by alpha cells, increases blood glucose levels, breakdown of glycogen
• Diabetes Mellitus


  the inability to produce enough insulin, blood glucose levels raise sharply
• Diabetes Type 1


  diagnosed in childhood, antibodies attack and destroy beta cells, not enough insulin production
• Diabetes Type 2


  develops over time, due to poor diet, cell receptors stop responding to insulin