Homework in – crossword sheet and Q’s on back

Neuron Questions• What is a neuron and what is its function?• Describe the main parts of a neuron and their

roles.• What is an action potential? • What does this mean: “an action potential is

an all or nothing event”?• Explain why neural communication is both

electrical and chemical.• What chemicals are involved in neural

communication?

Neuron:The cell of the nervous system.Dendrites, Cell body (or soma), Axon, Myelin sheath, Nodes of Ranvier, Terminal buttons, Synapse(s), Other structures?

Neurotransmitter (NT):A natural chemical in our nervous system that transmits infoAgonist:A drug (or poison) that enhances or mimics the activity of a NTAntagonist:A drug (or poison) that reduces the activity of a NT

Agonist: A drug (or poison) that enhances the activity of a NTAntagonist:A drug (or poison) that reduces the activity of a NT

Khan Academy: Agonists and Antagonists

Different neurotransmitters do different things!Acetylcholine (ACh):NT that affects learning and memory (in the brain), and movement (in muscles)Alzheimer’s patients have lower levels of ACh.

This American Life: A Trip Down Memory Lane

Botulinum poison:An antagonist that blocks the release of Ach, can paralyze diaphragm musclesand stop breathing

Botox: Before and After

Curare:Antagonist for Ach, leads to paralysis.S. American Indians use it for hunting.

Black widow spider poison:Ach agonist, causes flood of Ach, the Ach runs out

S. American Indian Hunters

Dopamine:Reward and motivationRewarding/pleasurable: eating, drinking, sexMotor control over voluntary Low levels Parkinson’s

Parkinson’s treatments can cause symptoms of schizophrenia (losing touch with reality, hallucinations, false beliefs, etc.)

Michael J Fox Interview

This American Life: Schizophrenia

Amphetamines and cocaine:Dopamine ____________ “High” arousal state followed by a crash

Other dopamine agonists:Painkillers, caffeine, nicotine

Serotonin:Emotional states, impulsiveness, dreaming

Norepinephrine:Alertness, higher mood level

Low levels of these NTs are related to depression, sadness/anxiety, food cravings, and aggressive behavior.

Antidepressants are ____________ for them, as well as drugs for eating disorders, OCD, and obesity.

Ex. Prozac, Paxil, Zoloft, Cymbalta, Pristiq, and Effexor

GABA (gamma-aminobutyric acid):the main inhibitory NT, keeps brain from getting too aroused/over-excitedLowers arousal/anxiety and helps regulate movement

Antianxiety drugs (tranquilizers) are ____________ for GABA

Glutamate:the main excitatory NT, memory storage and pain perception

High levels can cause neuron death, low levels can cause comaGlutamate may be linked to schizophrenia

Endorphins:NT involved in pain relief and pleasure

Higher endorphins levels have been found in runners post-marathons and in women during childbirth

Morphine and heroin mimic endorphins, and cause a release of dopamine

Is it linked to acupuncture?

Nervous System

Central NS (CNS)

Brain:Control

center for entire NS

Spinal Cord: Connects

brain and PNS, and enables

reflexes

Peripheral NS (PNS)

Somatic NS:Senses CNS

CNS Muscles

Autonomic NS:Involuntary,

controls organs and glands

Sympathetic NS:“Fight-or-flight”

systemControls body when

aroused

Parasympathetic NS:“Rest-and-digest”

systemControls the body during normal rest

state

Think deeply and answer completely. Do not copy the questions.Identify the parts labeled:1. A: ___________________2. B: ___________________3. C: ___________________4. What are neurotransmitters?5. What does an agonist do to a

neurotransmitter?6. What does an antagonist do to a

neurotransmitter?7. Would a message travel faster in an axon with

or without myelin?8. Respond to this quote:

Love is just a chemical being released in our brain.

A

BC