endocrine system

• What is homeostasis?

  Process of maintaining a constant internal environment
• Why is homeostasis vital for cells?

  It ensures a compatible internal environment for survival
• What does homeostasis balance?

  Excretion, nutrient intake, and metabolic consumption
• What must homeostasis maintain despite environmental changes?

  Oxygen, temperature, water, and nutrient levels
• Which body systems interact to maintain homeostasis?

  All body systems interact for homeostasis
• Which system has the major responsibility for regulating homeostasis?

  The endocrine system regulates homeostasis
• What is a hormone?

  A chemical regulating target cell activity

  
• How are hormones usually dispersed in the body?

  Through circulation in the blood
• What are glands?

  Organs that synthesize substances for release
• What is a receptor?

  A target for a hormone

  
• How do neurotransmitters differ from hormones?

  Neurotransmitters act locally at synapses
• What is the function of the exocrine system?

  Releases fluids into the lumen or outside
• What dual functions does the pancreas have?

  Endocrine and exocrine functions
• What hormones does the pancreas release?

  Insulin and glucagon
• Why do hormones only affect specific target cells?

  Only target cells have specific receptors

  
• How many different receptors does adrenaline have?

  Five different receptors
• What are the two types of hormones?

  Water soluble and lipid soluble hormones
• What is the major mineralocorticoid produced by the adrenal gland?

  Aldosterone
• Why can't water-soluble hormones diffuse across cell membranes?

  They cannot pass through lipid membranes
• How do lipid-soluble hormones affect gene expression?

  They bind to DNA and alter gene activity

  
• What is the role of the hypothalamus?

  Link between nervous and endocrine systems

  
• How does the hypothalamus control the pituitary gland?

  By releasing hormones that regulate it

  
• What are releasing hormones?

  Hormones that stimulate the anterior pituitary
• What is the function of the anterior pituitary?

  Synthesizes and secretes a wide range of hormones
• What hormone does the somatotroph secrete?

  Human Growth Hormone (hGH)
• What does Thyroid Stimulating Hormone (TSH) control?

  Regulates the Thyroid Gland's metabolism
• What does the adrenal cortex secrete?

  Corticosteroid hormones

  
• What is the function of aldosterone?

  Regulates fluid and electrolyte balance

  
• What happens when blood pressure or volume is low?

  Renin is secreted to start the RAA pathway
• What does Angiotensin II do?

  Causes vasoconstriction and increases blood pressure
• What is the role of ACE inhibitors?

  Reduce vasoconstriction and lower blood pressure
• What do glucocorticoids regulate?

  Metabolism and the body's stress response

  
• What is cortisol's role in the body?

  It is a primary glucocorticoid hormone

  
• How do glucocorticoids affect protein metabolism?

  They promote protein breakdown in the body
• What are the steps in the renin-angiotensin-aldosterone (RAA) pathway?

  1. Low blood pressure/volume causes renin secretion.
  2. Renin converts angiotensinogen to angiotensin I.
  3. Angiotensin I is converted to angiotensin II by ACE.
  4. Angiotensin II stimulates aldosterone secretion.
  5. Aldosterone causes Na+ and water retention.
  6. Increased blood volume and pressure result.
• What are the functions of the adrenal cortex and medulla?

  • Cortex: Secretes corticosteroid hormones (mineralocorticoids and glucocorticoids).
  • Medulla: Secretes adrenaline and noradrenaline.

  
• What are the differences between water-soluble and lipid-soluble hormones?

  • Water-soluble hormones:
  • Receptors outside target cells
  • Cannot diffuse through cell membranes
  • Lipid-soluble hormones:
  • Receptors inside target cells
  • Can diffuse through cell membranes
• What hormone is secreted by neurosecretory cells in the hypothalamus?

  Corticotropin releasing hormone (CRH)
• What does CRH stimulate in the anterior pituitary?

  Release of adrenocorticotropic hormone (ACTH)
• What is the primary glucocorticoid hormone produced?

  Cortisol (hydrocortisone)