6.2.1 Structure of Neurons

• Neurons are the basic units of the nervous system, and their main function is to transmit electrical signals
• Order the flow of signals in the nervous system using the three types of neurons:

  1️⃣ Sensory neurons receive signals from receptors

  2️⃣ Relay neurons transmit signals within the CNS

  3️⃣ Motor neurons carry signals to effectors
• How many main types of neurons are there?

  Three
• Dendrites receive signals from other neurons and transmit them towards the soma
• Neurons transmit electrical signals called nerve impulses.


  True
• What are neurons and their main function?

  Basic units; transmit signals
• Sensory neurons carry signals from receptors to the central nervous system
• What is the function of dendrites in a neuron?

  Receive signals
• What are the gaps in the myelin sheath called?

  Nodes of Ranvier
• The myelin sheath requires more energy to propagate nerve impulses than unmyelinated axons.

  False
• Interneurons carry signals between sensory and motor neurons within the central nervous system.

  True
• Match the type of neuron with its function:

  Sensory neurons ↔️ Carry signals from receptors to the central nervous system

  Motor neurons ↔️ Carry signals from the central nervous system to effectors

  Relay neurons ↔️ Carry signals between sensory and motor neurons
• The myelin sheath allows for faster transmission of nerve impulses.


  True
• Sensory neurons carry signals from receptors to the central nervous system
• Motor neurons carry signals from the central nervous system to effectors.


  True
• The soma, or cell body, contains the nucleus and other organelles
• Order the steps of nerve impulse transmission with and without myelin:

  1️⃣ Without myelin: Nerve impulses travel continuously along the axon

  2️⃣ With myelin: Nerve impulses 'jump' from one node of Ranvier to the next

  3️⃣ Without myelin: Slower transmission speed

  4️⃣ With myelin: Faster transmission speed
• What type of neurons carry signals from receptors to the central nervous system?

  Sensory neurons
• Nodes of Ranvier are gaps in the myelin sheath where the nerve impulse jumps
• What type of neurons carry signals from the central nervous system to muscles?

  Motor neurons
• Match the type of neuron with its function:

  Sensory neuron ↔️ Signals from receptors to CNS

  Motor neuron ↔️ Signals from CNS to effectors

  Relay neuron ↔️ Signals between sensory and motor neurons
• The myelin sheath insulates the axon to increase signal transmission speed.


  True
• What is the term for the process where nerve impulses 'jump' from one node to the next?

  Saltatory conduction
• Motor neurons carry signals from the central nervous system to effectors