Endocrine System

• endocrine system

  • one of the two systems that are responsible for communication and integration between body tissues
• hormones

  • chemical messengers
  • produced by endocrine glands and secreted into the bloodstream to reach body tissues
• target cell

  • cell targeted by a specific hormone
• steroid hormones

  • derived from cholesterol and are lipid-soluble
  • can cross the cell membrane to bind in their receptor in the cell’s cytoplasm or nucleus
• non-steroid hormones

  • derived from peptides or amino acids and are water-soluble
  • unable to cross the lipid membrane and must bind to receptors located on the surface of the cells
• hypothalamus

  • produce neuro-hormones which control the production of other hormones by the pituitary
  • links the nervous system and endocrine system
  • target cell: pituitary gland
  • function: Regulate hormones released by the pituitary gland
• pineal gland

  • hormone: melatonin
  • target cell: various tissues
  • function: Circadian rhythm, reproduction
• thyroid gland

  • control metabolic rates
  • hormones: thyroxine, triiodothyronine, calcitonin
  • target cell: most tissues, bone
  • functions: Metabolic Rate, Growth and Development. Lower plasma calcium, and phosphate
• parathyroid gland

  • produces hormones that regulate calcium and phosphorus
  • hormone: Parathyroid Hormone

  (PTH)

  • target cell: Bone, kidneys, intestines
  • function: Elevates plasma calcium and phosphate
• thymus

  • hormone: Thymopoietin
  • target cell: T-lymphocyte cells in body
  • function: Immune responses
• pancreas

  • produces insulin and glucagon that keep blood sugar levels in check
  • hormones: insulin, glucagon
  • target cells: muscle, liver
  • function:  1. Glucose utilization, lower blood glucose

   2. Elevates blood glucose
• intestinal mucosa

  • hormones: gastrin, secretin, cholecystokinin, somatostatin
  • target cells: stomach, pancreas, gallbladder, intestine
  • functions: 1. Acid secretion 2. Digestive secretion 3. Release of bile 4. Acid and intestinal secretion (inhibits)
• kidneys

  • hormone: Renin
  • target cell: blood vessel, smooth muscle, adrenal cortex
  • function: Blood pressure, aldosterone secretion
• ovaries

  • hormones: estrogen, progesterone
  • target cell: reproductive organs, uterus
  • functions: 1. Reproductive element, 2. Uterine condition
• uterus

  • hormone: Prostaglandin
  • target cell: corpus luteum
  • function: Breakdown of corpus luteum
• placenta

  • hormones: progesterone/estrogen, ECG, relaxin
  • target cell: 1. Corpus Luteum 2. Ovaries 3. Uterus, cervix, pelvic ligaments
  • function: 1-2. Maintenance of pregnancy 3.Inhibits uterine contraction, increase in distensibility.
• testes

  • hormone: testosterone
  • target cell: reproductive organ
  • function: Reproductive development and behavior
• posterior pituitary

  • holds on to the hormones released by the hypothalamus, and secretes them
  • does not make its own hormones
  • hormones: oxytocin, ADH
  • target cell: 1. Uterine smooth muscle, mammary gland 2. Kidney Tubules, smooth muscle in arterioles
  • functions: 1. Uterine contractions, milk let-down 2. Water excretion, blood pressure
• anterior pituitary

  •  can make own hormones
  • hormones: GH, prolactin, TSH, FSH, LH, ADCH
  • target cells: 1. All tissues

   2. Mammary Gland

  3. Thyroid Gland

  4. Ovaries/testes (tubules)

   5. Ovaries/testes (Leydig cells)

   6. Adrenal Cortex
• adrenal medulla

  • hormones: adrenaline, noradrenaline
  • target cell: all tissues
  • function: Metabolism: heart rate and output, response to stress and exercise
• adrenal cortex

  • hormones: cortisol, corticosterone, aldosterone
  • target cells: all tissues, kidneys
  • function: 1-2. Metabolism: response to stress and exercise

  3. Sodium, potassium and pH balance
• auxin

  • promotes cell elongation
• gibberellin

  • stimulates stem elongation
  • used to treat dwarfism in plants
• cytokinin

  • promotes cell division
  • delays aging of plants
• abscisic acid

  • inhibits plant growth
• ethylene

  • promotes fruit ripening
• melatonin

  • in charge of circadian rhythm, reproduction
• thyroxine & triiodothyronine

  • in charge of metabolic Rate, Growth and Development

   
•  Calcitonin

  • Lower plasma calcium, and phosphate
• PTH

  • Elevates plasma calcium and phosphate
• thymopoietin

  • Immune responses
• insulin

  • Glucose utilization, lower blood glucose
• glucagon

  • Elevates blood glucose
• gastrin

  • acid secretion
• secretin

  • digestive secretion
• cholecystokinin

  • release of bile
• somatostatin

  • Acid and intestinal secretion
• renin

  • Blood pressure, aldosterone secretion
• estrogen

  •  Reproductive element,
• progesterone

  • Uterine condition