Sensory, motor, and relay neurons

• What is the function of the myelin sheath around the axon?

  • Increases the speed of electrical signal transmission along the axon
  • Acts as an insulator to improve the efficiency of signal propagation
• What is the structure of sensory neurons?

  They have a simple, unipolar structure
• How do sensory neurons function in the body?

  They send information from senses to CNS
• What do motor neurons transmit signals from?

  Central nervous system (CNS)
• What do specialized synaptic end bulbs in sensory neurons release?

  Neurotransmitters
• What happens when you touch something hot?

  Receptors send an electrical signal to the brain
• What are the key structural components of a neuron?

  • Cell body (soma)
  • Dendrites
  • Axon
  • Myelin sheath
  • Node of Ranvier
  • Axon terminal
• How does the axon of sensory neurons differ from typical neurons?

  It connects directly to the cell body
• What is the name of the central part of a neuron?

  cell body (soma)
• How can sensory neurons be compared to messengers?

  They carry news from sense organs to the brain
• What role do sensory neurons play when touching a hot object?

  They inform the brain to move the hand
• How does the structure of a neuron allow for efficient signal transmission?

  • The myelin sheath insulates the axon to improve signal propagation speed
  • The nodes of Ranvier along the axon allow for saltatory conduction, further increasing transmission speed
  • The branching dendrites allow the neuron to receive signals from multiple sources
• What types of stimuli do sensory neurons respond to?

  Touch, light, or sound
• What is the name of the branching projections that receive signals from other neurons?

  dendrites
• What are sensory neurons?

  Nerve cells that transmit sensory information
• What types of information do sensory neurons carry?

  Information from senses like sight and touch
• What is the role of oligodendrocytes in the nervous system?

  • Oligodendrocytes produce the myelin sheath that insulates axons
  • This myelin sheath increases the speed of electrical signal transmission
• What do sensory neurons have that respond to stimuli?

  Special receptors
• What does CNS stand for in the context of sensory neurons?

  Central Nervous System
• What is the name of the long projection that extends from the neuron's cell body?

  axon
• How do sensory neurons transmit information?

  They pass it to the brain and spinal cord
• What structures are included in the CNS?

  Brain and spinal cord
• Where are the dendrites located in sensory neurons?

  At one end
• Where is the cell body (soma) located in sensory neurons?

  Off to the side
• What are the main components of sensory neurons?

  • Dendrites that detect stimuli
  • Long axon connecting to the cell body
  • Specialized synaptic end bulbs releasing neurotransmitters
• If the ventral root of a spinal nerve was damaged, how would that affect muscle movement?

  Muscle contraction and movement in the corresponding body region would be impaired
• What occurs when you decide to raise your hand?

  Motor neurons carry instructions to arm muscles
• What are motor neurons?

  Specialized nerve cells transmitting signals
• What is the signal direction for motor neurons compared to sensory neurons?

  • Motor Neurons: CNS to Muscles/Glands
  • Sensory Neurons: Senses to CNS
• What are the key structural features of a neuron that enable its function?

  • Soma: Contains the nucleus and integrates signals
  • Dendrites: Receive input signals from other neurons
  • Axon: Transmits output signals to other neurons
  • Myelin: Insulates the axon to increase signal transmission speed
  • Nodes of Ranvier: Gaps in the myelin that allow rapid, saltatory conduction
• How does the function of the relay neuron differ from the sensory and motor neurons shown in the image?

  The relay neuron transmits signals between the sensory and motor neurons, rather than directly detecting stimuli or controlling effectors
• If the dorsal root of a spinal nerve was damaged, how would that affect pain sensation?

  Pain sensation from the corresponding body region would be impaired
• What role do motor neurons play in hormone release?

  They communicate with glands to regulate release
• What are the main differences between relay neurons and sensory neurons?

  • Relay neurons have a central cell body
  • Sensory neurons have a cell body positioned to the side
  • Relay neurons connect other neurons efficiently
• How do the dendrites of motor neurons differ from those of sensory neurons?

  Motor neurons have multiple, direct dendrites
• What are the main components of motor neurons compared to sensory neurons?

  • Cell Body Position: Terminal (motor) vs. Lateral (sensory)
  • Dendrites: Multiple, direct (motor) vs. Single, indirect (sensory)
  • Axon Length: Long (both)
  • Myelin Sheath: Present (both)
• What covers the axon of motor neurons?

  Myelin sheaths
• Where is the cell body located in relay neurons?

  In the center
• What are Relay Neurons?

  Nerve cells that connect sensory and motor neurons
• What do motor neurons cause muscles to do?

  Contract