1. 10.2 Neuron Structure
Sponge: Set up Cornell Notes on pg. 5 Topic: 10.2 Neuron Structure Essential Question: What is the major function of the axon? Text:
2.1 Atoms, Ions, and Molecules
What is the major function of the axon?

2. Neurons and Neurotransmitters 5m35s
*Add info to picture bubble map

3. Objective
SWU: the general structure of a neuron SW: create a picture-bubble map of a neuron identifying the location and function of each part

4. Neuron Picture Bubble-Map
1. Draw/label a neuron on pg. 4. Make a “picture bubble map” explaining the function of each part of a neuron (p ) Include: dendrites, nucleus, cell body, axon, myelin sheath, Nodes of Ranvier, Schwann cells, axon terminal, synapse, neurotransmitter 2. Explain the function of each (keep short)

5. (aka action potential) Myelin sheath (covering/ only in PNS)
NEURON
Nucleus
Synapse
(gap between neurons)
Axon
terminals
Nerve Impulse
(aka action potential)
axon
Schwann Cells
(only in PNS)
Myelin sheath (covering/ only in PNS)
Dendrites
Cell body
(aka Soma)
Nodes of Ranvier
(only in PNS)
Neurotransmitters 4 5

6. Neurons
P.5
Neurons are nerve cells that are specialized to carry nerve impulses through an electrochemical process 

7. Nerve impulse aka action potential: Electrical signal that carries messages down the axon
Dendrites receive “message” from nearby neuron to be sent to next neuron

8. Dendrites: Receive nerve impulses
Provide receptive surfaces for communication
Usually highly branched

9. Cell body aka Soma: The cells life support center that contains the cytoplasm/organelles
Ex: mitochondria, lysosomes, golgi apparatus, and microtubules
Neurofibrils: A network of fine threads that extends into the axon for support—make up the axon
Nissl bodies: consist of rough endoplasmic reticulum (E.R.) needed for protein synthesis
Nucleus which contains the DNA of a cell

10. Axon: Specialized to conduct nerve impulses AWAY from the cell body to other neurons, muscles, and glands
Only one axon per neuron
Slender and cylindrical– can be VERY long

11. Axon cont’:
FOUND ONLY IN P.N.S.:
Schwann cells: Covers the axon and forms the myelin sheath
Gaps between Schwann cells are nodes of Ranvier (Ron-vee-ā)
Myelin sheath- is a insulating lipid (fatty) layer surrounding the axon
These work together to INCREASE THE SPEED of transmissions

12. Nerves: Bundles of axons

13. Axon terminals: the endings of a neuron
Location of ‘contact’ with other nerve or effector cells takes place
May have up to 10,000 connections from a single neuron
Neurotransmitters

14. Allows information to be transmitted from neuron to neuron
Neurotransmitters: Chemical signals released by axon terminal through the synaptic gap
Allows information to be transmitted from neuron to neuron
Neurotransmitters

15. Synapse or synaptic gap: Gaps between neurons

17. How neurons send signals:

18. How neurons send signals:
The function of a neuron is to receive INPUT "information" from other neurons, to process that information, then to send "information" as OUTPUT to other neurons.

19. How neurons send signals:
1. An action potential or nerve impulse is generated near the cell body portion of the axon. 

20. 2. This signal moves along the axon until it reaches the axon terminals. 
An action potential travels along the axon quickly, moving at rates up to 150 meters (or roughly 500 feet) per second. 

21. 2. This signal moves along the axon until it reaches the axon terminals. 

22. 2. This signal moves along the axon until it reaches the axon terminals. 

23. 2. This signal moves along the axon until it reaches the axon terminals. 

24. 2. This signal moves along the axon until it reaches the axon terminals. 

25. 2. This signal moves along the axon until it reaches the axon terminals. 
Dendrites of next neuron

26. 3. The signal ends at the axon terminals
3. The signal ends at the axon terminals. Axon terminals are where neurotransmission begins. 
Synapse (gap)
Axon terminal
Dendrites of next neuron

27. 3. The synaptic gap creates a physical barrier for the electrical signal carried by one neuron to be transferred to another neuron. 
Synapse (gap)
Axon terminal
Dendrites of next neuron

28. 3. Neurotransmitters transmit signals across the synapse, from one neuron to another "target" neuron, muscle cell, or gland cell
Synapse (gap)
Axon terminal
Dendrites of next neuron

29. 3. Neurotransmitters are released into the synaptic gap, where they are received by receptors on other neurons.
Synapse (gap)
Axon terminal
Dendrites of next neuron

31. Sponge: Set up Cornell Notes on pg. 7
Topic:
10.2 Three Types of Neurons
Essential Question: Describe the major difference between a sensory and motor neuron.
Text:
10.2 Three Types of Neurons
2.1 Atoms, Ions, and Molecules
Describe the major difference between a sensory and motor neuron.

32. A Closer Look at Neurons 4m49s
Add info to picture bubble map

33. Neurons
Neurons process ALL of the "information" that flows within, to, or out of the CNS. All of it!
All of the sensory information through which we are able to see, to hear, to smell, to taste, and to touch
All of the cognitive information through which we are able to reason, to think, to dream, to plan, to remember, and to do everything else that we do with our minds.
All of the motor information through which we are able to move

34. Sensory neurons
Interneurons
Motor neurons

35. Three Neuron Functions:
Some carry impulses into the brain or spinal cord
Others conduct impulses from neuron to neuron within the brain and spinal cord
Others carry impulses out of the brain or spinal cord

36. Three Types of Neurons 1m59s

37. 1. Sensory Neurons:
Located in PNS
The dendrites act as sensory receptors
Most are unipolar, some bipolar
Function: (PNS CNS) They gather information and carry impulses TO the brain and spinal cord

38. 2)Interneurons:
Located in CNS
Multipolar
Function: Receive signals from sensory neurons and relay them within the brain and spinal cord
Direct incoming sensory impulses to appropriate regions for processing/ interpreting/ decision making

39. 3)Motor neurons:
Located in the PNS
Multipolar
Function: (CNSPNS) Carry nerve impulses OUT of the brain or spinal cord to effectors (muscles and glands) to complete an action

40. Motor Neurons s

41. Key: Motor Neurons Effectors Receptors Sensory Neurons Interneurons
1._______________
2. ________________
Answer on p. 7
3. ______________
4. _____________
5._____________

42. Key: Motor Neurons Effectors Receptors Sensory Neurons Interneurons
1._______________
2. ________________
3. ______________
4. _____________
5._____________

43. 2. Sensory Neurons 3. Interneurons 4. Motor Neurons 1. Receptors
5. Effectors

44. Stimuli and Neurons 2m49- 4m 16s

45. Types of Neurons Picture Flow MAP
Sensory Neurons Interneurons Motor Neurons
Function
Location
Function
Location
Function
Location
Give a real life example (Tell a story)
Draw a picture for each
As short as possible
As short as possible
As short as possible
2. My brain interprets this information and identifies the sound as the phone ringing. I decide to answer the phone. This info is sent to my motor neurons
3. The motor neurons send nerve impulses to my muscles in my arm/hand which allows me to answer the phone.
1. The phone rings. The sensory neurons in my ear gather the sound information and send it to my CNS

46. 10.2 Classification of Neurons and neuroglial cells
Sponge: Set up Cornell Notes on pg. 9
Topic:
10.2 Classification of neurons and neuroglial cells
Essential Question: None.
Text:
10.2 Classification of Neurons and neuroglial cells
2.1 Atoms, Ions, and Molecules
Then turn to p. 6 for signature of HW

47. Table Talk Share your neuron “story” with your table Pick the best one
Be ready to share with class- pick reader

48. Structural Characteristics
Classification of Neurons and Neuroglial Cells
Neurons based on structure….(361-2/Table 10.1)
Bipolar Neurons
Unipolar Neurons
Multipolar Neurons
Neuroglial Cells in CNS (p.364-6/Table 10.2)
4. Astrocytes
5. Oligodendrocytes
6. Microglia
7. Ependyma
Neuroglial Cells in PNS (364/Table 10.2)
8. Satellite Cells
9. Schwann Cells
Title
Illustration
Function
Location
CNS/PNS
Specific location?
Structural Characteristics
Shape
# of processes
Other important information

49. Neuron Gallery Walk We will go on a gallery walk to gather our notes
3 mins each (30 mins)
Use your books to fill in any missing information

50. Classification of Neurons – Structural Differences
1. Bipolar neurons:
Only 2 processes
One is an axon/ one is a dendrite
Location: Found in PNS sensory neurons
Eyes, nose, ears
Function: They gather information and carry impulses into the brain and spinal cord

51. 2. Unipolar neurons:
1 process extending from its cell body
Divides into two branches
One branch enters the brain or spinal cord
Location: Found in PNS sensory neurons
Gather in specialized masses of nerve tissue called ganglia outside the brain and spinal cord
Function: They gather information and carry impulses into the brain and spinal cord

52. 3. Multipolar Neurons:
Many processes
One is an axon, the rest dendrites
Location: Found within the CNS
Function: They transmit nerve impulses between neurons within the brain and spinal cord
AND conduct nerve impulses out of the brain and spinal cord to muscles or glands

53. Types of Neuroglial Cells
Neuroglial cells: provide support to the neurons.
In much the same way that the foundation, framework, walls, and roof of a house prove the structure through which run various electric, cable, and telephone lines, along with various pipes for water and waste, not only do glia provide the structural framework that allows networks of neurons to remain connected, they also attend to the brain's various house keeping functions (such as removing debris after neuronal death).
It is worth noting that there are as many as 50 times more glia than neurons in our CNS!

54. Types of Neuroglial Cells in the PNS
Schwann Cells:
Location: PNS
Function: Produce myelin that wrap tightly around the axons of peripheral neurons and Speed up neurotransmissions

55. 2. Satellite Cells:
Small cuboidal cells that surround clusters of neuron cell bodies called ganglia
Function: Support ganglia in the PNS

56. Types of Neuroglial (Neu-rag-lial) Cells in the CNS
Astrocytes:
Star shaped
Abundant (many) processes
Location: Found in CNS between neurons and blood vessels
Functions:
Provide support & hold structures together
Respond to injury of brain tissue and form scar tissue
Transports substances between blood vessels and neurons
Communicate with one another, and with neurons
Aide in metabolism of certain substances (glucose)
Regulate the concentrations of important ions (potassium)

58. 2. Oligodendrocytes: (Ollie-go-dendro-cytes)
Fewer processes than Astrocytes
Occur in rows along myelated axons
May provide myelin for many axons at one time
Functions:
Form myelin sheaths within the brain and spinal cord
Produce nerve growth factors

59. 3. Microglia: (Mycro-glea)
Small
Have very few processes
Scattered through the CNS
Functions:
Support neurons
Phagocytize bacterial cells and cellular debris (immune protection)
Multiply whenever the brain or spinal cord is inflamed due to injury or disease

60. 4. Ependyma: (uh-pen-dĭma)
Cuboidal or columnar in shape
Found in the inner lining of the ventricles of the brain and the central canal of the spinal cord
Function:
They form a porous layer through which substances diffuse freely between the interstitial fluid of the brain and the cerebrospinal fluid within the ventricles

62. Crash Course: Nervous System Part I 9m36s