CHAPTER 12

• What are the two kinds of cells found in nervous tissue?

  Neurons and neuroglia (glial cells)
• What is the primary function of neurons?

  Specialized for intercellular communication
• What role do neuroglia play in the nervous system?

  Support and protect neurons
• What does the central nervous system (CNS) consist of?

  The brain and spinal cord
• What are the functions of the central nervous system?

  Integrate, process, and coordinate sensory information and motor commands
• What types of data does the nervous system process?

  Sensory data from inside and outside the body
• What do motor commands control?

  The activity of peripheral organs, such as skeletal muscles and glands
• What higher functions of the brain are mentioned?

  Intelligence, memory, learning, and emotion
• What are the main components of the nervous system?

  • Brain and spinal cord
  • Receptors of sense organs (eyes, ears, etc.)
  • Nerves connecting to other systems
• What are the functions of the nervous system?

  Receive information, process it, and initiate responses
• What does the afferent division of the PNS do?

  Carries sensory information from receptors to the CNS
• What are receptors?

  Structures that detect stimuli
• What types of receptors are mentioned?

  Visceral, somatic, and special senses
• What does the efferent division of the PNS do?

  Carries motor commands from the CNS to effectors
• What are effectors?

  Muscles, glands, and adipose tissue that respond to motor commands
• What is the somatic nervous system (SNS) responsible for?

  Controlling skeletal muscle contractions
• What is the autonomic nervous system (ANS) responsible for?

  Controlling smooth muscle, cardiac muscle, adipose tissue, and glands
• What are the two subdivisions of the ANS?

  Sympathetic division and parasympathetic division
• What does the peripheral nervous system (PNS) consist of?

  All nervous tissue outside the CNS
• What is the role of nerves in the PNS?

  Carry sensory information and motor commands
• What connects to the brain?

  Cranial nerves
• What connects to the spinal cord?

  Spinal nerves
• What is the enteric nervous system (ENS)?

  Neurons in the walls of the digestive tract
• What does the ENS do?

  Initiates and coordinates local visceral reflexes of the digestive tract
• How can the ENS be influenced?

  By the sympathetic and parasympathetic divisions of the PNS
• What is a neuron?

  The basic functional unit of the nervous system
• What is the function of a neuron's excitable plasma membrane?

  To send and receive signals
• What are the main parts of a neuron?

  Cell body (soma), axon, and dendrites
• What is the axon?

  A single, long cytoplasmic process that propagates electrical signals
• What is the axoplasm?

  The cytoplasm of the axon
• What is the axolemma?

  The plasma membrane of the axon
• What is the axon hillock?

  The thick region that attaches the initial segment of the axon to the cell body
• What are collaterals in a neuron?

  Branches of the axon
• What are telodendria?

  Fine branches of the distal axon or collaterals
• What are axon terminals?

  Expanded tips of the telodendria
• What are dendrites?

  Short and highly branched processes extending from the cell body
• What do dendrites do?

  Receive information from other neurons
• What are dendritic spines?

  Fine processes on dendrites
• What are the structural classifications of neurons?

  • Anaxonic neuron
  • Bipolar neuron
  • Unipolar neuron
  • Multipolar neuron
• What is the function of the cell body (soma) in a neuron?

  Contains the nucleus and organelles necessary for the neuron's function