Human Endocrine System

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Human Endocrine System
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Endocrine Overview

• Hormones- chemical messengers travel through body
• Target cell or organ- organ or cells that a
  hormone affects

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Control of Hormone Release

• Negative feedback mechanism- hormone release is
  triggered by stimulus, rising levels of hormone
  inhibit further release
• Endocrine stimuli-
• Hormonal- hormones stimulate the release of
  others
• Humoral- blood stimulates release of hormones
• Neural- nerves stimulate hormone release

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Anterior Pituitary Gland

• Growth Hormone (GH)- affects growth of skeletal
  muscles and bones
• Prolactin (PRL)- stimulates milk production after
  pregnancy
• Gonadotropic- regulates hormone activity of sex
  organs
• Also effects adrenal cortex and thyroid hormone
  release

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Posterior Pituitary

• Oxytocin- helps during pregnancy
• Antidiuretic hormone (ADH)- inhibits urine
  production
• Alcohol inhibits ADH causing increased output of
  urine

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Thyroid Gland

• Thyroid hormone
• Controls the rate at which glucose is burned
• Calcitonin
• Decreases calcium levels in blood deposits on bone

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Parathyroid Gland

• Parathyroid hormone (PTH)- regulates Ca2 in
  blood
• If Ca2 level drops bones is broken down

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Adrenal Gland

• Adrenal Cortex
• Releases hormones that regulate mineral content
  in blood
• Adrenal Medulla
• Produces epinephrine and norepinephrine
• Helps with stressful situations

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Pancreas

• Insulin- increases glucose uptake into cells and
  stores in liver
• Glucagon- stimulates breakdown of glucose stores
  in the liver

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Pineal Gland

• Melatonin
• Establishes bodys day/ night cycle

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Thymus

• Thymosin
• Programs T cells

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Gonads

• Androgens (male)- sperm formation, development of
  male char
• Estrogens (female)- development of female char