A&P Chapter 11 Notes

What Are The Types Of Nervous Systems?

• central nervous system (CNS) = brain and spinal cord

• peripheral nervous system (PNS) = everything outside of brain and spinal cord!

  • somatic nervous system (SNS) = voluntary movement

  • autonomic nervous system (ANS) = involuntary movement

What Are The Job Types Of The Peripheral Nervous System?

• somatic = voluntary movement, things you can control

  • moving your arm

• autonomic = involuntary movement, things your body does by itself

  • heart beat

for autonomic, think like auto pilot

What Are The Directions Of The Central Nervous System?

• sensory = afferent, messages going to the brain

  • when you touch something, and it’s hot

• motor = efferent, messages going from the brain

  • message telling you to move your hand away

for afferent, think “a” does not mean away, it means to

What Are The Moods Autonomic Nervous System?

• sympathetic = fight or flight

• parasympathetic = rest and digest

What Does A Multipolar Neuron Consist Of?

• dendrites = branch like receptors that receive messages

• cell body with nucleus = the main part containing the nucleus

• axon = long trunk that sends messages

• axon hillock = where the cell body meets the axon, is also the decision spot (to send message or not?)

• schwann cell (myelin sheath) = creates insulation around axon (like rubber on a wire)

• node of ranvier = gaps in the myelin sheath that help speed things up

• axon terminal = knob like endings that send messages

• synaptic vesicles = tiny bubbles in the axon terminal that store and release chemicals

• neurotransmitters = the chemicals that carry messages

think of a neuron like a tree with a long trunk

Cluster Terminology

• peripheral nervous system

  • ganglion, nerve

• central nervous system

  • nuclei, tract

Ganglion

Cluster of cell bodies in the peripheral nervous system

Nuclei

Cluster of cell bodies in the central nervous system

Nerve

Bundles of axons in the peripheral nervous system

Tract

Bundle of axons in the central nervous system

What Are The Types Of Neurons?

• unipolar

• bipolar

• multipolar

Unipolar Neuron

• sensory = feel things

Bipolar Neuron

• special senses = eyes, ears, nose

Multipolar Neuron

• motor = thinking cells

the most common type of neuron

What Are The Neuroglia Cells In The Central Nervous System?

• astrocytes = protect the brain (blood brain barrier)

• oligodendrocyte = make up myelin sheath

• microglia = clean up

• ependymal = produce cerebral spinal fluid/brain fluid

Neuroglia cells are like helpers and cleaners

What Are The Neuroglia Cells In The Peripheral Nervous System?

• schwann cells = make up myelin sheath

• satellite = support neurons

Neuroglia cells are like helpers and cleaners

What Are The Types Of Ion Channels?

• leakage = always a little open

• gated = open/close when needed

What Are The Types Of Gated Ion Channels?

• voltage = opens with electricity change, change in membrane potential

  • Na+ and K+ (salt and potassium)

• ligand = opens with chemicals (neurotransmitters)

• mechanical = opens with touch/pressure

What Does Graded Membrane Potential Consist Of?

• occurs at the dendrite

• varies in strength

• travels short distances to the axon hillock

What Does Action Potential Consist Of?

• occurs at the axon hillock

• one strength

• travels long distances

• all or none principle (it either happens or it doesn’t)

What Are The Speeds Of Action Potential?

• no myelin = unmyelinated

  • slow (continuous conduction)

• with myelin = myelinated

  • fast, jumping node to node (saltatory conduction)

What Is The Action Potential Process?

1. Resting membrane potential = K+ in (potassium), Na+ out (sodium)

2. Depolarization = Na+ in (sodium)

3. Repolarization = K+ out (potassium)

4. Hyperpolarization = too much K+ out (potassium)

What Is The Neurophysiology Of A Synapse?

• presynaptic membrane = sender

  • releases neurotransmitters (calcium triggers release)

• post synaptic membrane = receiver

  • has receptors

What Is The Outcome Of A Synapse?

• inhibitory post synaptic potential (ISPS)

  • calms = hyper-polarization (too much K+ out)

• excitatory postsynaptic potential (EPSP)

  • excites = depolarization (Na+ in)