hormones

• Difference between steroid and peptide hormones:

  Steroid:

  1. enter the cell pass the plasma membrane
  2. bind to receptor in cytoplasm
  3. act directly on DNA
  4. directly affect gene transcription

  Peptide:

  1. do not enter the cell
  2. bind to receptor on plasma membrane surface
  3. act through messenger/cAMP
  4. influence enzyme activity/protein kinase
  5. requires ATP
• Difference between endocrine and exocrine glands: Endocrine glands secrete hormones into the bloodstream; Exocrine glands secrete hormones onto a body surface
• Function of prolactin:

  1. growth and development of the mammary gland
  2. lactation/synthesis of milk
  3. maintenance of milk secretion
• List two hormones produced by the posterior pituitary gland:

  1. oxytocin
  2. ADH
• How do steroid hormones work:

  1. endocrine glands secrete hormones directly into the bloodstream
  2. pass through the plasma membrane of target cell
  3. bind to receptor proteins in cytoplasm - forming a receptor-hormone complex
  4. complex enters the nucleus
  5. promotes the transcription of specific genes
• How do peptide hormones work:

  1. bind to receptors in the plasma membrane
  2. which activates a cascade of reactions
  3. mediated by a secondary messenger (cyclic AMP)
  4. results in activation of enzymes