the nervous system (B5)

• What two organ systems do humans rely on for communication?

  Nervous system and endocrine system
• What is the main function of the nervous system?

  To coordinate behavior and respond to surroundings
• What are the main topics to know about the nervous system?

  • Structure of a nerve cell
  • Structure of the nervous system
  • How a reflex arc works
• What is another name for a nerve cell?

  Neuron
• How are neurons adapted to carry electrical impulses?

  They are long, thin, and have branch connections
• What is the role of a synapse in neuron communication?

  It connects two nerve cells for impulse transfer
• What happens when an electrical impulse reaches the end of a nerve?

  Chemicals are released to trigger another impulse
• How does the nervous system process sensory information?

  It receives information through sensory neurons
• What does CNS stand for?

  Central Nervous System
• What is the function of motor neurons?

  To send impulses to effectors like muscles
• What are effectors generally in the nervous system?

  Muscles or glands
• What is a reflex arc?

  • Nerve pathway for unconscious reflexes
  • Example: moving hand from a hot surface
  • Rapid and automatic response
• What is the role of receptor cells in a reflex action?

  To detect stimuli like pressure or heat
• What happens to the impulse in the spinal cord during a reflex action?

  It transfers to a relay neuron
• What does a motor neuron do in a reflex arc?

  It carries the impulse to an effector
• Why are reflexes beneficial?

  They allow rapid and automatic responses
• How do synapses function in the transmission of impulses?

  They convert electrical signals to chemical signals
• What is the process of a reflex action when touching a sharp object?

  1. Stimulus detected by receptor cells
  2. Sensory neuron carries impulse to spinal cord
  3. Relay neuron transfers impulse within spinal cord
  4. Motor neuron sends impulse to effector
  5. Effector (muscle) contracts to withdraw hand
• What should you be able to describe by the end of the video?

  Structure of the nervous system and reflex arc
• What is homeostasis?

  Maintaining constant internal conditions
• What are the components of an automatic control system?

  Stimulus, receptor, coordination center, effector, response
• What are the two parts of the nervous system?

  Central nervous system and peripheral nerves
• What does the central nervous system consist of?

  Brain and spinal cord
• What is the role of receptors in the nervous system?

  Detect stimuli and send impulses
• What are neurons?

  Nerve cells that transmit impulses
• What is the function of effectors?

  Bring about a response
• What are the two types of effectors mentioned?

  Muscles and glands
• How does the nervous system help humans?

  Enables reaction to surroundings and behavior coordination
• What is the reflex arc?

  A pathway for reflex actions
• What happens when you touch a hot object?

  The reflex arc is activated
• What is the first step in the reflex arc when touching a hot object?

  The stimulus is detected by a receptor
• What type of neuron carries impulses to the central nervous system?

  Sensory neuron
• What occurs at the synapse between the sensory neuron and relay neuron?

  A chemical is released to trigger an impulse
• What is the role of the relay neuron?

  Transmit impulses within the central nervous system
• What happens at the synapse between the relay neuron and motor neuron?

  A chemical triggers an electrical impulse
• What does the motor neuron do in the reflex arc?

  Transmits impulses to the effector
• What is the effector in the reflex arc when touching a hot object?

  The muscle that contracts
• What is the response when you touch a hot object?

  Pulling the hand away
• Why are reflex actions important?

  They are automatic and rapid for protection
• How does the central nervous system usually function in decision-making?

  It coordinates actions based on brain decisions