Nervous System quiz

More questions about Nervous System

These visible examples show the question style. LearnClash turns the full topic into ranked duels and spaced repetition.

1. 1 Easy

   Where in the human body does the longest single nerve cell end?

   Answer: In the big toe

   Why: Those sciatic axons run from the base of the spinal cord to the big toe and can top a metre, the longest cells in the human body.

2. 2 Medium

   Why do local anesthetics prevent the nervous system from transmitting pain?

   Answer: Blocking sodium channels

   Why: Lidocaine must cross the nerve membrane uncharged to block the sodium channel from the inside, and it grips hardest on the channels firing most.

3. 3 Hard

   What periodic gaps in myelin sheaths enable rapid signal transmission?

   Answer: Nodes of Ranvier

   Why: A node is only about 1 micrometre long, yet leaping from node to node lets myelinated fibres exceed 100 m/s, against 0.5 to 2 m/s without myelin.

4. 4 Easy

   Which structures primarily receive the chemical signals arriving at a neuron?

   Answer: Dendrites

   Why: The word dendrite comes from the Greek word for tree, perfectly describing their highly branched appearance.

5. 5 Medium

   What must a neurotransmitter cross to stimulate another neuron?

   Answer: Synaptic cleft

   Why: The synaptic cleft is incredibly narrow, typically measuring only about twenty to forty nanometers wide.

6. 6 Hard

   How does the nervous system generate the resting membrane potential of neurons?

   Answer: Sodium-potassium pump activity

   Why: The sodium-potassium pump consumes massive amounts of cellular energy to maintain the electrical charge necessary for nerve firing.