Nervous and Endocrine Systems/Behavior

  1. Cnidarians
    Simple nervous systems, very basic nerve net modified neurons that allow impulses to travel up and down body (simple movement)
  2. Annelid Worms
    • Primitive brains (ganglia) fuses groups of neuron cell that extend axons down length of worm
    • Ventral nerve cod, segmented ganglia down body
  3. All animals, three main components
    • Sensory Input
    • Motor output
    • integration
  4. Nerve cell/neuron
    Basic functional unit of mammal nervous systems
  5. cell body
    contains nucleaus
  6. Dendrites
    • extension of cytoplasm from cell body that recieve chemical sign and maintain signal as electrical signal
    • highly branched and receive signals from many neurons at once
  7. Schwann
    • Seperate cells from the neurons, secrete myelin as insuation for nerve cells that help signals move faster down axon
    • In CNS the equivalent of schwann is oligodendrocyte, which send off myelinated sheets all at once
  8. Myelin
    • Insulation for nerve cells that help signals move faster down axon
    • Complex of containing membrane of nearby schwann cells 
    • Nerves that loose myelin cannot transport messages fast enough
  9. Nodes of ranvier
    space along myelinated axons where schwann cells have not laid covering
  10. Axon
    main elongated extension of the cell body through electrical signal travels one direction from cell body toward synaptic knob
  11. Synaptic Knob
    Release neurotransmitters
  12. Neurotransmitters
    Chemicals that communicate with surrounding nerve cells
  13. Astrocytes
    • In CNS are more numerous than neurons
    • These cells stick to various parts of neurons and break down and remove neurotransmitters
    • Chemically engulf debris
  14. Ependymal Cells
    Line the fluid filled cavities of the brain and spinal cord and secrete cerebrospinal fluid
  15. Why are cells negatively charged
    • DNA is negatively charged, negative charged phosphate groups
    • many proteins are negative
    • Sodium potassium pumps kick out three positive sodiums, and bring in two positive potassiums
  16. Cation
  17. Anion
    Negative ion
  18. Repolarization
    • Outflow of positive charge, return to negative charge
    • Reestablishment of separation of charge across a membrane
    • Sodium channel gets inactive, and cell is impermeable to sodium
    • Potassium gates open, allowing potassium to move out
  19. At resting potential is:
    Outside the neuron is:
    Inside the Neuron there is:
    • Polarized at resting, meaning there is a seperation of charge across a membrane
    • Outside: high sodium concentration, low potassium concentration
    • Inside:low sodium concentration, HIgh potassium
  20. Depolarization
    • A reduction in the seperation of charge across a membrane
    • Sudden permeability of the membrane to sodium ions via opening of voltage gated channels
    • Rapid influx of sodium ions
    • Rapid depolarization of the membrane that produces a reversal in the internal charge from negative to positive
  21. Hyperpolarization
    • so many potassium ions flow out, that the cell goes below -70milivolts and becomes more negatively charged than usual
    • An increase in separation of charge across a membrane
  22. Threshold
    • Stimilus to a neuron that causes the opening of voltage gated channels
    • Causes depolarization but must depolarize to a certain level (threshold) to fire
  23. Refractory Period
    once action potential flows down the axon, it slowly becomes negatively charged. Once sodium channels are inactive for a period--> Refractory perio
  24. Larger signals =______Neurons
    Larger signals use more neurons, to produce a large response, but have same action potential
  25. Presynaptic and post synaptic
    before and after synapse
  26. electrical signal in axon becomes a _____
    Becomes a chemical signal in synapse and then back to electrical in new neuron
  27. Action potential
    • charge difference across membrane
    • Electrochemical gradient that accompanies the wave of depolarization along the membrane
    • i.e. nerve impulse
    • Happens when stimulus reaches a threshold
  28. What happens as action potential reaches synaptic knob
    voltage gated calcium channels open and rapid influx of calcium ions cause membrane bound vesicles filled with neurotransmitters merge to presynaptic membrane and release contents in to synapse
  29. Acetylcholine
    • Will bind to membrane receptors on the postsynaptic dendrites or cell body and cause opening of ligand gated channels  on post synaptic cell
    • starts action potential all over again
  30. inhibitory neurotransmitters
    • Are used in pain pathways to moderate amount of pain you feel
    • Hyperpolarize the cell to stop action potential from reaching post synaptic membrane
  31. Motor Neurons
    Sensory Neurons
    • Motor Neurons -CNS to PNS
    •    Only excite 
    • Sensory Neurons-PNS to CNS 
    •    Inhibit and excite
  32. Afferent Neurons
    Carry info about external and internal environment to brain and spinal cord
  33. Efferent Neurons
    Carry commands from brain/spinal cord to muscles or glands ect
  34. Nerves
    Bundles of axons covered with connective tissue
  35. Sensory Nerve, Motor nerve, and mixed
    • Sensory nerves carry only sensory fibers
    • Motor nerves carry only motor fibers
    • mixed nerves are both
  36. Ganglia in CNS are called
  37. PNS
    • Somatic and autonmic
    • Autonomic is sympatheic and parasympatheic
    • Volunary movement
  38. Brain function
    interpret sensory info forming motor plans, cognitive functions
  39. Forebrain
    Telenecephalon and diencephalon
  40. Telecephalon
    • Right and left hemispheres
    • Each hemispheres contains (frontal, parietal, temporal, occipital lobe)
  41. Cerebral Cortex
    • High convoluted gray matter that can be seen on surface of the brain
    • Processes sensory input
    • R and L communicate wit each other through corpus callosum of cortex
  42. Corpus Callosum
    R and L communicate wit each other through
  43. Diencephalon
    Thalamus and hypothalamus
  44. Thalamus
    Relay and integration center for spinal cord and cerebral cortex
  45. Hypothalamus
    • Controls visceral functions
    • Hunger, thirst, sex
    • Plays important role in endocrine system
    • Secretes releasing hormones which pushes pituitary to release stimulating hormones
  46. Midbrain
    • relay center for visual and auditory impulses
    • motor control
  47. Hindbrain
    • posterios part of brain
    • consists of cerebellum, pons, and medulla
  48. Cerebellum
    Motor impulses, balance, and hand eye cordniation
  49. pons
    relay center for cortex communication with cerebellum
  50. Medula
    Vital functions like breathing, heart rate
  51. Brain stem
    Mid brain, pons, medulla
  52. Spinal cord function and four sections
    • incorperates all sensory info below head
    • Simple motor responses
    • (top) cervical, thoracic, lumbar, and sacral (bottom)
  53. Stomatic
    innervates skeletal muscles, body system
  54. Monosynaptic reflex
    • reflex involves one neuron
    • Ex: knee jerk reaction
  55. Polysynaptic reflex
    • More than one neuron, withdrawal reflex
    • ex: step on nail, one leg pulls up and other extends to retain balance
  56. Autonomic NS
    • involuntary nervous system
    • Parasympathetic and sympathetic NS
    • Regulates body internal environment without conscious control
    • Regulates blood pressure, gastrointestinal, respiration and reproduction
  57. Sympathetic NS
    • Fight of flight
    • Increase blood pressure, decrease gut activity, release adrenaline
  58. Parasympathetic NS
    • Rest and digest, conserve energy and resotre body to resting state
    • Lower heart rate, and increase gut activity
  59. Proprioceptors
    Transmit info regarding position of body in 3d space, also in inner ear
  60. Exteroceptors
    Sense thing in external environment (light sounds taste pain temp)
  61. Eye
    Detects photons and transmits info about shape, intensity, color, and shape to brain
  62. Sclera
    White of eye
  63. Choroid
    Behind sclera, helps supply retina with blood
  64. Retina
    inner most layer of eye that contains photoreceptors
  65. Cornera
    Transparent layer at front of eye that bends and focuses light onto lens
  66. Iris
    • Muscle that controls opening and closing of pupil
    • Responds to intensity of  light
  67. Ciliary Muscles
    Control shape of lense, and focus image onto retina
  68. Cones
    • Respond to high intensity light
    • Sensitive to color
  69. Rods
    • Low intensity light
    • Night vision
  70. Optic Nerve
    • Axons of ganglion cells bundle together to conduct visual info into brain
    • Where optic nerve exits eye there is a blind spot
  71. Fovea
    • Desly packed with cones
    • Important for high acuity vision on retina
  72. Ear
    • Converts sound E, i.e. pressure waves into impulses perceived by brain as sound
    • maintains balance
  73. Outer Ear
    Pinna, auditory cannal
  74. Tympanic Membrane
    • Eardrum, separates outer and middle ear
    • Vibrates at same frequency as incoming sound
  75. Ossicles
    • Amplify the stimulus and transmits it through oval window, to fluid of inner ear
    • Three bonds, malieus, incus, and stapes
  76. Inner ear
    Cochlea and semi circular canals
  77. Cochlea
    • Contains organ of corti, has hair cells
    • Vibrations of ossicles exert pressure on fluid in cochlea and stimulate hair cells
    • Pressure turns into action potential which travels into auditory nerve to brain
  78. Semicircular Canals
    • are three perpendicular canals  that are filled with fluid an hair cells
    • the fluid covers hair cells on one side and the brain can determine where the head is
  79. Taste
    • Outer surface of taste bud is taste pore which has microvili
    • Taste are sour salty sweet bitter and brothy
  80. Smell
    • Olfactory receptors are in upper aret of nostril and have olfactory hairs, or cilia
    • substance enters nose and binds to cillia
  81. Endocrine system
    • gland synthesize and secrete chemical hormones which enter blood stream
    • Hormonal signaling can last for days
    • Work mostly vis negative feed back loops
  82. Pituitary Glans
    • Anterior and posterior have different hormones
    • Most travel in blood and cause other glands to release their hormones
    • Master Gland
  83. Growth Hormone
    • Anterior pituitary
    • Stimulates bone and muscle growth
  84. Prolactin
    • Anterior pituitary
    • Stimulates milk production and secretion
  85. Adrenocrotictropic Hormone (ACH)
    • Anterior Pituitary
    • Stimulates adrenal cortex to synthesize glucorticoids
  86. Thyroid Stimulus Hormone
    • Anterior pituitary
    • thyroid to produce thyroid hormone
  87. Lutenzing Hormone(LH)
    • Anterior pituitary
    • Stimulates ovolulation, and testosterone in men
  88. Follicle Stimulating Hormone (FSH)
    • Anterior pituitary
    • Stimulates follicule maturation in females and spermatogenesis in males
  89. Oxytocin
    • Produced in Hypothalamus
    • Stored in posterior pituitary
    • Uterine contractions during labor and milk secretion
  90. Vasopression (ADH)
    • Hypothalamus
    • Stored in posterior pituitary
    • Water reabsorbed in kidneys
  91. Thyroid Hormone
    • Thyroid
    • Stimulates metabolic activity
  92. Calcatonin
    • Thyroid
    • Decreases calcium in blood
  93. Parathyroid
    • Parathyroid
    • Increases calcium in blood
  94. Glucocorticoids
    • Adrenal 
    • increase blood glucose
  95. Mineralocortocoids
    • Adrenal
    • Increase water reabsorption in kidney
  96. Epinephrine and Norepinephrine
    • Adrenal Medula
    • Increase blood glucose and heart rate
  97. Glucagon
    • Pancreas
    • stimulates conversion of glycogen to glucose in liver
  98. Fixed Action Patterns (FAP)
    • Innate behaviors not learned 
    • neurologically wired 
    • Triggered by a sign stimulus
  99. Imprinting
    Environmental patterns or objects presented become stamped in to an animals behavioral response
  100. Habituation
    • Repeated stimulation results in decrease in responsiveness
    • Allows constant stimui to become ignored 
    • ex: background noise
  101. Sensitization
    Repeated stimulation results in more responsiveness
  102. Associative Learning
    • Animal links two events or stimuli as related
    • Conditioned reflex
  103. Two parts of conditioning reflexes
    • Established innate reflex (ex food make you salivate)
    • Neutral stimulus (bell)
    • Conditioned reflex (bell makes you salivate)
  104. Operant conditoin
    Uses reward, can be positive or negative conditioning
Card Set
Nervous and Endocrine Systems/Behavior
Biology GRE