Careful Coordination

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Careful Coordination

• Vocabulary words
• Nervous system
• Neurons
• Glial cells
• Hypothalamus
• Physiological processes
• Endocrine
• Endocrine system
• Hormones

• Vocabulary words
• -- Receptors
• Vasopressin
• Pituitary gland
• Feedback Negative feedback
• Blood pressure
• Constrict
• Positive feedback

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Careful Coordination

• Nervous system
• The nervous system regulates many automatic
  responses.
• The nervous system is responsible for all of the
  bodys voluntary responses also.
• The nervous system is made up of all the nervous
  tissue, the brain, and spinal column.
• The nervous system plays a key role in
  coordinating internal balance.

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• The nervous system contains two types of cells
• Neurons produce and send nerve impulses
• Glial cells protect, support and insulate neurons
• Brain is the control center for the nervous
  system.
• The brainstem directs the critical, automatic
  responses necessary to sustain life.
• Hypothalamus is a specialized part of the brain
  that regulates a variety of physiological
  processes..
• Water balance, body temperature, feeding and
  sleep as well as help to regulate several
  endocrine functions

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• Endocrine system
• Made up of glands and cells that produce and
  release chemical messengers called hormones,
  directly into the blood
• Many hormones work to regulate internal balances
  like water and blood sugar balance.
• Hormones are carried by the blood past every cell
  of the body but only target cells and organs
  are able to respond to a specific hormone.
• The target cells have a receptor (protein that
  fit the shape of a specific hormone molecule) on
  their membrane (like a lock target cell
  receptor and key hormone)

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• Example of how the nervous system and the
  endocrine system work together to maintain
  homeostasis.
• Hormones control a variety of processes by
  binding to target cell receptors. We will use
  dehydration as our example.
• Sensors in the hypothalamus detect the increase
  in sodium ion concentration in the blood.
  (remember dehydration causes this increase in
  sodium ion concentration).
• Specialized neurons in the hypothalamus, which
  extend into the pituitary gland, respond to the
  increase in sodium concentration by causing the
  pituitary gland to produce and release a hormone
  called vasopressin.

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• 3. Vasopressin is a hormone that is carried
  throughout the body in the blood.
• 4. The target cells for vasopressin are the cells
  of the kidney.
• 5. The vasopressin causes the membranes of the
  kidneys tubules to become more permeable to
  water.
• 6. This means more water can be reabsorbed into
  the blood and less water is secreted to the
  urine.
• 7. The result is prevention of further
  dehydration.

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Example of how the nervous system and the
endocrine system work together to maintain
homeostasis.

• At the same time, the nervous system also works
  to restore water balance.
• Parts of the nervous system sense the increase in
  sodium ion concentration and respond by
  triggering thirst.
• Homeostasis involves the coordination of many
  body systems and a combination of automatic
  responses (physiological responses) and voluntary
  behaviors (behavioral responses).

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• The body uses feedback systems to maintain an
  internal balance ad to regulate responses to
  changing conditions
• Negative feedback systems work to shut offthe
  response that the body had to being out of
  balance
• When the body senses dehydration it responds by
  producing more vasopressin and reabsorbing more
  water.
• When the body senses that the amount of water in
  the body is at the appropriate level, it signals
  the hypothalamus to reduce that amount of
  vasopressin that is released into the blood.