Reflex actions

What is a reflex action?

• A) A slow, voluntary response to a stimulus.

• B) An automatic and rapid response to a stimulus.

• C) A learned response that requires conscious thought.

• D) A reaction that only occurs in the brain.

How does the structure of a neuron contribute to its function in transmitting electrical signals?

• A) The axon is wrapped in myelin to prevent electrical leakage, speeding up signal transmission.

• B) The dendrites are essential for controlling the speed of action potentials.

• D) The axon ensures that neurons communicate with each other.

• D) The synapse ensures that neurons communicate with each other.

What is the primary function of the reflex arc?

• A) To allow voluntary muscle movement.

• B) To process sensory information in the brain.

• C) To enable quick and automatic responses to stimuli.

• D) To regulate blood flow during physical activity.

What might happen if the myelin sheath on a neuron was damaged? How would this affect signal transmission?

• A) The neuron would generate more neurotransmitters, improving communication.

• B) The electrical signals would travel faster, resulting in better communication between neurons.

• C) The electrical signals would travel slower, which could lead to neurological problems 

• D) The neuron would be unable to transmit signals at all.

Which of the following is NOT part of the reflex arc?

• A) Sensory neuron

• B) Motor neuron

• C) Interneuron

• D) Respiratory neuron

Which statement best explains the role of dendrites in neuronal communication?

• A) Dendrites transmit action potentials to the axon.

• A) Dendrites transmit action potentials to the axon.

• C) Dendrites generate neurotransmitters.

• D) Dendrites form synaptic vesicles for neurotransmitter release.

If a person experiences damage to their sensory neurons, what could be the potential consequences on their ability to interact with the environment?

• A) They would experience increased pain sensitivity.

• B) They would have difficulty sensing external stimuli like temperature, touch, or pain.

• C) They would have improved reflexes due to faster signaling.

• D) Their movement would be unaffected, but memory would be impaired.

Which of the following best describes the difference between electrical and chemical signals in neurons?

• A) Electrical signals are used to transmit information within a neuron, while chemical signals transmit information between neurons.

• B) Electrical signals are slower than chemical signals.

• C) Electrical signals occur at synapses, while chemical signals occur in axons.

• D) Electrical signals are used to store information, while chemical signals are used for thinking.

When a person touches a hot object and quickly pulls their hand away, which of the following is true?

• A) The signal first travels to the brain before the hand is pulled away.

• B) The motor neuron immediately sends a signal to the hand muscles via interneurons without involving the brain.

• C) The sensory neuron directly communicates with the motor neuron, bypassing the spinal cord.

• D) The reflex action takes longer because the brain processes the information first.

What would happen if the nodes of Ranvier were absent or damaged?

• A) The speed of the action potential would increase dramatically.

• B) The action potential would move more slowly.

• C) The neuron would no longer be able to communicate with other neurons.

• D) The neuron would send signals in the wrong direction.