We've all experienced that moment at the doctor's office where they tap our knee and our leg just shoots out completely involuntarily. This is an example of a reflex. These are neural pathways that control involuntary instantaneous movements in response to some type of stimulus. Often, you'll hear this referred to as a reflex arc. Now, the sensory neurons will actually carry information from the stimulus into the dorsal side of the spine. So here we have the dorsal side, this is the ventral side. Let me pop my head out of the way so you can see what I've written. Ventral, dorsal, basically, think dorsal like the fin which is on the back of dolphins. So, the sensory neuron is going to carry information towards the spine and it's going to enter the dorsal side, and its cell body will be part of that dorsal root ganglion we talked about a little while ago. And it's either going to synapse directly on a motor neuron or an interneuron that will, in turn, synapse on a motor neuron. So basically, some type of stimulus is going to signal it and it's going to in turn signal either the interneuron or motor neuron. In this case, we have an interneuron right here before the motor neuron, and it's essentially going to result downstream in the motor neuron sending a signal to a muscle and causing some type of movement in response. Motor neurons will leave the ventral side of the spine, as you can see, and they'll synapse on a muscle, right, neuromuscular junction to create some type of movement. The basic outcome of all this is a very fast response to a potentially damaging stimulus. This is your body's way of protecting itself, and what's important to note is that none of this involves the brain. It does go into the spine, so it does involve the central nervous system, but no processing occurs in the brain with these reflex arcs. So here in our example, you can see this guy is touching a hot flame, which is not a good idea, I don't recommend it, and that's going to cause a reflex arc which will result in him pulling his hand away from the flame very quickly. You know, this is like if you step on a sharp object, you just shoot your foot up before you even have a chance to realize what happened. And again, these reflex arcs are just very simple neural pathways that allow for a quick response to some type of stimulus, generally a stimulus that signals some type of potential damage or injury. So with that, let's flip the page.
Table of contents
- 1. Introduction to Biology2h 40m
- 2. Chemistry3h 40m
- 3. Water1h 26m
- 4. Biomolecules2h 23m
- 5. Cell Components2h 26m
- 6. The Membrane2h 31m
- 7. Energy and Metabolism2h 0m
- 8. Respiration2h 40m
- 9. Photosynthesis2h 49m
- 10. Cell Signaling59m
- 11. Cell Division2h 47m
- 12. Meiosis2h 0m
- 13. Mendelian Genetics4h 41m
- Introduction to Mendel's Experiments7m
- Genotype vs. Phenotype17m
- Punnett Squares13m
- Mendel's Experiments26m
- Mendel's Laws18m
- Monohybrid Crosses16m
- Test Crosses14m
- Dihybrid Crosses20m
- Punnett Square Probability26m
- Incomplete Dominance vs. Codominance20m
- Epistasis7m
- Non-Mendelian Genetics12m
- Pedigrees6m
- Autosomal Inheritance21m
- Sex-Linked Inheritance43m
- X-Inactivation9m
- 14. DNA Synthesis2h 27m
- 15. Gene Expression3h 20m
- 16. Regulation of Expression3h 31m
- Introduction to Regulation of Gene Expression13m
- Prokaryotic Gene Regulation via Operons27m
- The Lac Operon21m
- Glucose's Impact on Lac Operon25m
- The Trp Operon20m
- Review of the Lac Operon & Trp Operon11m
- Introduction to Eukaryotic Gene Regulation9m
- Eukaryotic Chromatin Modifications16m
- Eukaryotic Transcriptional Control22m
- Eukaryotic Post-Transcriptional Regulation28m
- Eukaryotic Post-Translational Regulation13m
- 17. Viruses37m
- 18. Biotechnology2h 58m
- 19. Genomics17m
- 20. Development1h 5m
- 21. Evolution3h 1m
- 22. Evolution of Populations3h 52m
- 23. Speciation1h 37m
- 24. History of Life on Earth2h 6m
- 25. Phylogeny2h 31m
- 26. Prokaryotes4h 59m
- 27. Protists1h 12m
- 28. Plants1h 22m
- 29. Fungi36m
- 30. Overview of Animals34m
- 31. Invertebrates1h 2m
- 32. Vertebrates50m
- 33. Plant Anatomy1h 3m
- 34. Vascular Plant Transport2m
- 35. Soil37m
- 36. Plant Reproduction47m
- 37. Plant Sensation and Response1h 9m
- 38. Animal Form and Function1h 19m
- 39. Digestive System10m
- 40. Circulatory System1h 57m
- 41. Immune System1h 12m
- 42. Osmoregulation and Excretion50m
- 43. Endocrine System4m
- 44. Animal Reproduction2m
- 45. Nervous System55m
- 46. Sensory Systems46m
- 47. Muscle Systems23m
- 48. Ecology3h 11m
- Introduction to Ecology20m
- Biogeography14m
- Earth's Climate Patterns50m
- Introduction to Terrestrial Biomes10m
- Terrestrial Biomes: Near Equator13m
- Terrestrial Biomes: Temperate Regions10m
- Terrestrial Biomes: Northern Regions15m
- Introduction to Aquatic Biomes27m
- Freshwater Aquatic Biomes14m
- Marine Aquatic Biomes13m
- 49. Animal Behavior28m
- 50. Population Ecology3h 41m
- Introduction to Population Ecology28m
- Population Sampling Methods23m
- Life History12m
- Population Demography17m
- Factors Limiting Population Growth14m
- Introduction to Population Growth Models22m
- Linear Population Growth6m
- Exponential Population Growth29m
- Logistic Population Growth32m
- r/K Selection10m
- The Human Population22m
- 51. Community Ecology2h 46m
- Introduction to Community Ecology2m
- Introduction to Community Interactions9m
- Community Interactions: Competition (-/-)38m
- Community Interactions: Exploitation (+/-)23m
- Community Interactions: Mutualism (+/+) & Commensalism (+/0)9m
- Community Structure35m
- Community Dynamics26m
- Geographic Impact on Communities21m
- 52. Ecosystems2h 36m
- 53. Conservation Biology24m
45. Nervous System
Central and Peripheral Nervous System
Video duration:
3mPlay a video:
Related Videos
Related Practice
Central and Peripheral Nervous System practice set
- Problem sets built by lead tutorsExpert video explanations