Nervous and Endocrine System

Function of Nervous Regulation: Control and coordinate your response to your environment using electrical impulses Impulse- electrical messages carried by neurons Nerve cells (Neurons) - specialized cells that carry electrical impulses throughout an organism

3 steps to a nervous response Receive stimulus through receptor Cause effector to respond to impulse

Neuron Cell Structure: Cell body Contains nucleus Controls the growth of cell Generates electrical impulse

Neuron Cell Structure: Dendrite Fibers that receive impulses from other neurons Impulse is carried toward the cell body

Neuron Cell Structure: Axon Long fiber that extends away from the cell body Covered with Schwann cells (myelin) to insulate the impulse Conducts impulse away from the cell

Neuron Cell Structure: Synapse Gap between the dendrite of one neuron and the axon of another Neurotransmitter chemical is used to bridge the gap and conduct the impulse

Neuron Types: Motor Neurons Carry an impulse from the brain/spinal cord to the muscle cells Sensory Neurons Senses are generated here Sense a stimulus and send impulse to the brain/spinal cord

Involuntary response Use parts of the brain other than cerebrum Reflex- simple response that goes quickly to the spinal cord and back to the effector (muscle) NO Brain involvement!

Two main parts Central Nervous System (CNS) Brain and Spinal Cord

Two main parts Central Nervous System (CNS) Brain Cerebrum- 2 hemispheres (halves) 3 functions-sensory (senses), motor (voluntary movement), associative (memory, learning, & thought) Cerebellum- Controls all voluntary movements and some involuntary movements Coordinates balance Coordinates movement with cerebrum

Central Nervous System

Two main parts Central Nervous System (CNS) Brain Brainstem: Medulla and Pons Controls heartbeat, breathing, blood flow and coughing

Central Nervous System Spinal Cord Connects peripheral nerves to brain Controls reflexes

Peripheral Nervous System -all nerves that are NOT part of brain or spinal cord Composed of sensory and motor neurons Carries impulses to and from the CNS

ENDOCRINE SYSTEM

Chemical Regulation: Endocrine system Function: regulate metabolism, homeostasis, growth and reproduction, use chemical messages or hormones Effect on the body: Hormones are specific to a target organ or tissue to stimulate or inhibit Effect of hormone- last minutes to hours or even years

Organs of the Endocrine System : GLANDHORMONE(S)FUNCTION IN THE BODY PinealmelatoninDaily sleep and wake cycles Pituitary (Master gland) TSH,ACTH, Growth Hormone, FSH, LH, Prolactin/ oxytocin, vasopressin Controls other glands ThyroidThyroxine, calcitonin Overall body metabolism, blood calcium levels

Organs of the Endocrine System: ParathyroidparathormoneCalcium and phosphate metabolism ThymusthymosinStimulate T-cells in immune system PancreasInsulin, glucagon Blood sugar (glucose)

Organs of the Endocrine System: AdrenalEpinephrine (adrenaline) & norepinephrine, cortisol, aldosterone Stimulate nervous system “fight or flight” mechanism, stress response, sodium balance Ovary/ testisEstrogen, progesterone, testosterone Sperm and egg production, secondary and primary sex characteristics

Every cell in body ProstaglandinSecreted in response to injury and affect metabolic activities such as heart beat, blood pressure & immune response

Example: TSH in Pituitary gland Thyroid makes thyroxine hormone Thyroxine, too high so negatively affect pituitary gland therefore TSH Lower TSH means lower thyroxine Pituitary TSH Thyroid Thyroxine

Nervous and Endocrine Disorders Parkinson’s Disease- certain areas of brain die off affecting muscle movement Huntington’s Disease- genetic disease in which neurons waste away or degenerate in brain- uncontrolled movements to inability to care for oneself Alzheimer’s Disease- memory loss from brain cell death

Cushing’s Disease- too much cortisol Hyperthyroidism- thyroid secretes too much Diabetes Mellitus- insulin secreting cells don’t secrete Nervous and Endocrine Disorders