1. Ch. 43 Review Warm-Up Contrast the functions of B cells and T cells.
What are memory cells?
How do vaccines work?
How does HIV affect the immune system?

2. Warm-Up Draw and label the parts of a neuron.
Describe saltatory conduction.
Explain how a nerve impulse is transmitted across a neuron.

3. Warm-Up What happens at the synapse?
Choose 1 neurotransmitter. Describe its action.
What is the role of the following structures in the human brain?
Brainstem
Cerebellum
Cerebrum
Corpus callosum

4. Chapters 48 & 49 Campbell Biology – 9th ed.
Nervous Systems
Chapters 48 & 49
Campbell Biology – 9th ed.

5. You must know The anatomy of a neuron.
The mechanisms of impulse transmission in a neuron.
The process that leads to release of neurotransmitters, and what happens at the synapse.
How the vertebrate brain integrates information, which leads to an appropriate response.
Different regions of the brain have different functions.

6. Organization of the Nervous System
Central nervous system (CNS) = brain + spinal cord
Peripheral nervous system (PNS) = nerves throughout body
Sensory receptors: collect info
Sensory neurons: body  CNS
Motor neurons: CNS  body (muscles, glands)
Interneurons: connect sensory & motor neurons
Nerves = bundles of neurons
Contains motor neurons +/or sensory neurons

11. Peripheral Nervous System
Somatic
nervous
system
Autonomic
nervous
system
Sympathetic
division
Parasympathetic
division
Enteric
division

13. Neuron = dendrite + cell body + axon

14. Neuron cell body: contains nucleus & organelles
dendrites: receive incoming messages
axons: transmit messages away to other cells
myelin sheath: fatty insulation covering axon, speeds up nerve impulses
synapse: junction between 2 neurons
neurotransmitter: chemical messengers sent across synapse
Glia: cells that support neurons
Eg. Schwann cells (forms myelin sheath)

15. Schwann cells and the myelin sheath

16. BioFlix: How Neurons Work

17. Membrane Potential: difference in electrical charge across cell membrane
Microelectrode
–70 mV
Voltage
recorder
Reference
electrode

18. Voltage-Gated Ion Channels
The Na+/K+ pump (using ATP) maintains a negative potential inside the neuron.
Voltage-Gated Ion Channels

19. Action potentials (nerve impulses) are the signals conducted by axons
Resting potential: membrane potential at rest; polarized
Na+ outside, K+ inside cell
Voltage-gated Na+ channel = CLOSED
Nerve impulse: stimulus causes a change in membrane potential
Action potential: neuron membrane depolarizes
All-or-nothing response
Na+ channels open
K+ channels open
Na+ enters cell
K+ leaves cell
Inside of neuron axon becomes more - again (= repolarized)
Inside of neuron axon becomes more + (=polarized)

26. Conduction of an action potential

27. Action Potential The resting potential of a neuron is -70 mV
Stimulus (and depolarization) must reach the Threshold of -55 mV in order for an action potential to occur = “all or none” response

28. Nerve Impulse Animation

29. Saltatory conduction speed: 120 m/sec
Saltatory conduction: nerve impulse jumps between nodes of Ranvier (unmyelinated gaps)  speeds up impulse
Saltatory conduction speed: 120 m/sec

30. Cell communication: neurotransmitter released at synapses Axon (presynaptic cell)  Dendrite (postsynaptic cell)

31. Neurotransmitters
Chemicals released from vesicles by exocytosis into synaptic cleft
Diffuse across synapse
Bind to receptors on neurons, muscle cells, or gland cells
Broken down by enzymes or taken back up into surrounding cells
Types of neurotransmitters:
Excitatory: speed up impulses by causing depolarization of postsynaptic membrane
Inhibitory: slow impulses by causing hyperpolarization of postsynaptic membrane

33. Examples of Neurotransmitters
Acetylcholine (ACh): stimulates muscles, memory formation, learning
Epinephrine: (adrenaline) fight-or-flight
Norepinephrine: fight-or-flight
Dopamine: reward, pleasure (“high”)
Loss of dopamine  Parkinson’s Disease
Serotonin: well-being, happiness
Low levels  Depression
GABA: inhibitory NT
Affected by alcohol

34. TGIF!
Have out your “Endocrine System” Homework Reading + Questions for me to check.
Complete the Warm-up (use your notes!)
Read the board for tonight’s HW assignment.
We MAY have important visitors today so do not be out of your seat, on your phone, or working on things for other classes.

35. WARM-UP GRADE
Each group should discuss the assigned warm-up question below and come to a consensus on the best answer choice. Be ready to explain to class. You may NOT discuss with other groups. Today’s warm-up grade will be whole-class determined.
Table # 1 2 3 4 5 6 7 8
Warm-up Question # 9 18
19 & 34
If your group is not 100% confident, you may ask permission to “phone a friend” BUT we will be docked ½ point from overall score.

36. Let’s Visualize
Nerve Cell Communication Animation (from Life Sciences Learning Center)

37. Nerve Cell Communication
“Lab” Activity
Work in Pairs
Each pair needs:
1 Sending AND 1 Receiving neuron
Baggie of White card labels & Blue card labels
Baggie of beads and pink +/1 strips
Lab sheet for each person
Read and follow directions. Raise your hand when you reach the “Teacher Checks.”

38. When you Finish Turn in Activity to Tray
Return bags to box on front table
Return Sending and Receiving Neurons to Correct Pile
Pick up:
HW POGIL
Notes sheet

39. POGIL: Neuron Structure
This is for Homework!
Due Monday

40. BioFlix: How Synapses Work

41. Evolution of Nervous Systems

42. Vertebrate brain is regionally specialized
Major Regions: forebrain, midbrain, hindbrain

43. Forebrain  cerebrum
Midbrain  brainstem
Hindbrain  cerebellum

44. Human Brain Structure Function Cerebrum Brainstem Cerebellum
Information processing (learning, emotion, memory, perception, voluntary movement)
Right & Left cerebral hemispheres
Corpus callosum: connect hemispheres
Brainstem
*Oldest evolutionary part*
Basic, autonomic survival behaviors
Medulla oblongata –breathing, heart & blood vessel activity, digestion, swallowing, vomiting
Transfer info between PNS & CNS
Cerebellum
Coordinate movement & balance
Motor skill learning

45. Human Brain Structure Function Cerebrum Brainstem Cerebellum
Information processing (learning, emotion, memory, perception, voluntary movement)
Right & Left cerebral hemispheres
Corpus callosum: connect hemispheres
Brainstem
*Oldest evolutionary part*
Basic, autonomic survival behaviors
Medulla oblongata –breathing, heart & blood vessel activity, digestion, swallowing, vomiting
Transfer info between PNS & CNS
Cerebellum
Coordinate movement & balance
Motor skill learning

46. Human Brain Structure Function Cerebrum Brainstem Cerebellum
Information processing (learning, emotion, memory, perception, voluntary movement)
Right & Left cerebral hemispheres
Corpus callosum: connect hemispheres
Brainstem
*Oldest evolutionary part*
Basic, autonomic survival behaviors
Medulla oblongata –breathing, heart & blood vessel activity, digestion, swallowing, vomiting
Transfer info between PNS & CNS
Cerebellum
Coordinate movement & balance
Motor skill learning

47. Human Brain Structure Function Cerebrum Brainstem Cerebellum
Information processing (learning, emotion, memory, perception, voluntary movement)
Right & Left cerebral hemispheres
Corpus callosum: connect hemispheres
Brainstem
*Oldest evolutionary part*
Basic, autonomic survival behaviors
Medulla oblongata –breathing, heart & blood vessel activity, digestion, swallowing, vomiting
Transfer info between PNS & CNS
Cerebellum
Coordinate movement & balance
Motor skill learning

48. Grey matter: neuron cell bodies, unmyelinated axons White matter: fatty, myelinated axons

49. Reflexes Simple, automatic response to a stimulus
Conscious thought not required
Reflex arc:
Stimulus detected by receptor
Sensory neuron
Interneuron (spinal cord or brain stem)
Motor neuron
Response by effector organ (muscles, glands)

50. Reflex Arc
Reflex Arc (from Life Sciences Learning Center)

51. Knee-jerk reflex

52. Components of a Reflex Arc

53. Time to Practice & Review
Complete all parts of the packet using your notes.
Use the textbook Ch if needed.

54. The Adolescent Brain