BIO

• Nervous System

  • center of all mental activities (learning, memory, thinking and speech)
  • receives, examines and processes data - initiates response
  • controls and regulates all activities
  • coordinates functions of all organs
  • regulates and maintains homeostasis
  • keeps us in touch of environment
• Stimuli - anything that evokes a person's reaction
• homeostasis - body's ability to maintain constant internal equilibrium, CNS and Endocrine
• Neuron - basic cellular unit of the nervous system, transmit impulse
• Neuron

  1. Sensory neurons - receives info and transmits impulse to SC or brain
  2. Motor neurons - impulse from brain or SC to muscles and glands
  3. Interneurons - scattered, Sensory to motor
• Synapse - space where impulse travels
• Neurotransmitters - chemicals that help transport message
• Nissl bodies - body sites for protein synthesis and other
• Axon - neuron without Nissl body, transmit impulse to motor neurons
• Myelin sheath - surrounds axon
• Nerve fiber - axon + myelin sheath
• Neurilemma - outside CNS, produce myelin sheath
• Fiber tract - bundled nerve fibers, SC and brain
• Nerve - bundled nerve fiber outside CNS
• Epineurium - fibrous sheath of cells that surrond nerve
• dendrite - shorter extension of cell body, increase surface area
• Hormonal secretion - enable the propagation of nerve impulses from synapse, from synaptic knobs once an electric impulse is received
• Acetylcholine - from motor neurons to skeletal muscles
• Norepinephrine - respond to stress
• Dopamine - related to muscular activity
• Serotonin - operates in bodily functions such as mood, regulation, consciousness, emotions
• Melatonin - sleep and wake cycles
• Reflex - involuntary and automatic response to stimulus, sensory to SC, interneurons in SC to motor - Reflex arc
• 1. Motor neurons - impulse from brain or SC to muscles and glands
• Interneurons - scattered, Sensory to motor
• CNS - brain + spinal cord
• brain - 100 B neurons, do not regenerate, protected by skull

  spinal cord - protected by vertebral column
• meninges - three layers of membranes
• 1. Sensory neurons - receives info and transmits impulse to SC or brain
• 1. Sensory neurons - receives info and transmits impulse to SC or brain
• Hindbrain - medulla oblongata - upright position and regulating involuntary functions (breathing and circulation)
• hindbrain - cerebellum - fine muscle movement and balance
• hindbrain - pons - bridge to midbrain, sleep regulation
• midbrain - reticular formation - relays signals (eyes and ears), general levels of lethargy or liveliness
• forebrain - cerebrum or cerebral cortex - seat of intelligence
• forebrain - thalamus - sorts and relays incoming and outcoming information, area if sensory integration
• forebrain - hypothalamus - pleasurable activities, eating and drinking, emotions, stress and feelings
• Spinal cord - large, ropelike segment of nerve tissues extending from medulla oblongata to the vertebral column, connector mechanism from spinal reflexes and between peripheral nervous system and brain
• Peripheral nervous system - brain and sc are connected w rest of body through this
• PNS - 12 pairs of cranial nerves from brain and 31 pairs of spinal nerves