2.5.2 Reflex Actions

• What is the role of sensory neurons in a reflex arc?

  Carry signals to spinal cord
• Steps in the sequence of events in a reflex arc

  1️⃣ Receptor senses a stimulus

  2️⃣ Sensory neuron carries signal to spinal cord

  3️⃣ Relay neuron connects sensory and motor neurons

  4️⃣ Motor neuron carries response to effector

  5️⃣ Effector performs the action
• Why are reflex actions faster than voluntary actions?

  They bypass the brain
• Pulling your hand away from heat is an example of a reflex
• What is the main role of sensory neurons in a reflex arc?

  Transmit stimulus information
• Reflex actions require conscious control.

  False
• Reflex actions are sufficient with just the spinal cord.
• What is the effector in a reflex arc?

  Muscle or gland
• What is a reflex arc?

  A response to stimuli
• The relay neuron connects the sensory and motor neurons in the spinal cord
• Order the components of a reflex arc from stimulus detection to response:

  1️⃣ Receptor detects stimulus

  2️⃣ Sensory neuron carries signal

  3️⃣ Relay neuron connects in spinal cord

  4️⃣ Motor neuron carries response

  5️⃣ Effector performs action
• What is the effector in a reflex arc?

  Muscle or gland
• Why are reflex actions important for survival?

  React quickly to threats
• What are reflex actions?

  Involuntary, automatic responses
• Relay neurons are located in the brain.

  False
• Reflex actions are important for survival
• What are three examples of reflex actions?

  Hand withdrawal, blinking, knee-jerk
• The purpose of reflex actions is to achieve a specific goal.

  False
• Voluntary actions require conscious control.

  True
• What are reflex actions?

  Involuntary, automatic responses
• How does the speed of reflex actions compare to voluntary actions?

  Faster
• What is the role of sensory neurons in a reflex arc?

  Carry stimulus signal
• Motor neurons carry the response to the effector.
• The receptor in a reflex arc senses the stimulus
• What is the role of the effector in a reflex arc?

  Performs the reflex action
• What is the primary function of sensory neurons in a reflex arc?

  Transmit stimulus information
• Match the neuron type with its location:

  Motor Neuron ↔️ From spinal cord to effector

  Sensory Neuron ↔️ From receptor to spinal cord

  Relay Neuron ↔️ Spinal cord
• Reflex actions are faster than voluntary actions.
• The neural pathway that enables a reflex action is called a reflex arc
• What is the function of motor neurons in a reflex arc?

  Carry response to effector
• Why are reflex actions important for protecting us from harm?

  They are quick responses
• Reflex actions do not require conscious control
• Which part of the nervous system is sufficient for reflex actions?

  Spinal cord
• Match the component of a reflex arc with its function:

  Receptor ↔️ Senses the stimulus

  Sensory Neuron ↔️ Carries signal to spinal cord

  Relay Neuron ↔️ Connects sensory and motor neurons

  Motor Neuron ↔️ Carries response to effector

  Effector ↔️ Performs the action
• Sequence the events in a reflex arc

  1️⃣ Receptor senses a stimulus

  2️⃣ Sensory neuron carries the signal to the spinal cord

  3️⃣ Relay neuron connects sensory and motor neurons

  4️⃣ Motor neuron carries the response to an effector

  5️⃣ Effector performs the action
• Relay neurons are located within the spinal cord.


  True
• Match the example with the type of reflex action

  Pulling hand away from heat ↔️ Protective reflex

  Blinking ↔️ Automatic reflex

  Knee-jerk reflex ↔️ Basic reflex
• The sensory neuron carries the signal from the receptor to the effector.

  False
• Reflex actions allow the body to react quickly without conscious thought or processing in the brain
• Relay neurons facilitate communication between sensory and motor neurons.