nervous system

• What are the two organ systems that help large multicellular organisms communicate?

  The nervous system and the endocrine system
• Why do large multicellular organisms need a communication 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 whole nervous system
  • How a reflex arc works
• What is another name for a nerve cell?

  Neuron
• What is the primary function of neurons?

  To carry electrical impulses from one point to another
• How are neurons adapted to their function?

  They are long, thin, and have many branch connections
• What is a synapse?

  A connection between two nerve cells
• What happens when an electrical impulse reaches the end of a nerve cell?

  It causes the release of chemicals that diffuse across the synapse
• What is the role of sensory neurons in the nervous system?

  To carry information from receptors to the central nervous system
• What does the central nervous system consist of?

  The brain and spinal cord
• What is the function of motor neurons?

  To send impulses from the central nervous system to effectors
• What are the components of the nervous system and their functions?

  • Sensory neurons: Carry information from receptors to CNS
  • Central nervous system (CNS): Processes information and sends orders
  • Motor neurons: Transmit impulses to effectors (muscles or glands)
• What is a reflex arc?

  A nerve pathway that underlies unconscious reflexes
• Why are reflexes beneficial?

  They allow rapid and automatic responses to stimuli
• What happens when you touch a hot object?

  A sensory neuron carries the impulse to the spinal cord
• What is the role of receptor cells in the reflex arc?

  To detect stimuli such as pressure or temperature
• What happens in the spinal cord during a reflex action?

  The impulse is transferred to a relay neuron
• What is the final step in a reflex arc?

  The motor neuron sends an impulse to an effector
• What occurs at synapses during nerve signal transmission?

  The electrical signal is converted to a chemical signal
• What is the purpose of the nervous system?

  To detect changes and respond to them