Endocrine System

• What is the primary function of the endocrine system?

  It is another communication system in the body.
• How does the endocrine system transport signals?

  It uses blood to transport signals (hormones).
• What does it mean that the signal released into the blood is transported throughout the body?

  It means that hormones can affect various parts of the body.
• How does the speed of the endocrine system compare to the nervous system?

  The endocrine system is slower than the nervous system.
• What are the two types of glands in the endocrine system?

  Endocrine glands and exocrine glands.
• What is the function of endocrine glands?

  They contain cells that produce a hormone and secrete it straight into the blood.
• How do endocrine glands differ from exocrine glands?

  Endocrine glands are ductless.
• What do exocrine glands produce?

  They produce a chemical which is not directly released into the blood.
• What is the role of the duct in exocrine glands?

  The duct carries the secretion to another place.
• What are the two types of hormones?

  Protein and peptide hormones, and steroid hormones.
• Why can't protein and peptide hormones cross the plasma membrane?

  They are not lipid soluble.
• Where do protein and peptide hormones bind?

  They bind to receptors on the plasma membrane.
• What is a characteristic of steroid hormones?

  They are lipid soluble and can pass through the plasma membrane.
• How do steroid hormones act upon the cell?

  They act upon the DNA in the nucleus.
• What allows hormones to travel around the body without affecting other cells?

  Some cells have complementary receptors on their plasma membrane (target tissues).
• What happens when a hormone binds to its receptor?

  The cell then responds to the signal.
• What are the key differences between protein/peptide hormones and steroid hormones?

  • Protein and peptide hormones:
  • Not lipid soluble
  • Do not cross the plasma membrane
  • Bind to receptors on the plasma membrane

  
  

  • Steroid hormones:
  • Lipid soluble
  • Can pass through the plasma membrane
  • Act upon DNA in the nucleus
• How do the functions of endocrine glands differ from exocrine glands?

  • Endocrine glands:
  • Ductless
  • Secrete hormones directly into the blood

  
  

  • Exocrine glands:
  • Have ducts
  • Produce chemicals not released directly into the blood