Chapter 3 functional units New

Page 1: Introduction to Brain and Behavior

• Overview of the nervous system's functional units.

• Title: "Introduction to Brain and Behavior" by Myers, DeWall, Kolb, Whishaw, Teskey.

• Focus on the understanding of neural units.

Page 2: Internal Structure of a Cell

• Historical Context: Debate in the early 1900s

• Key Contributions:

  • Golgi's view: Nervous system as a "nerve net".

  • Cajal's hypothesis: Nervous system composed of discrete cells; supported neuron hypothesis.

    • Neurons are the units of brain function.

Page 3: Two Views of a Cell

• Cajal's use of the Golgi stain demonstrated discrete cells in the nervous system, contrary to Golgi's integrated view.

• Cajal's neuron theory: Neurons recognized as the fundamental units of brain function and organization.

Page 4: Basic Structure of a Neuron

• Neuron Structure:

  • Soma (Cell Body): Core region of the neuron.

  • Dendrites: Branching extensions collecting information from other cells.

  • Axon: Main root carrying messages away from the cell body; typically has one axon but numerous dendrites.

Page 5: The Basis of Information Processing: Neurons

• Neurons work in groups, producing behaviors through networks.

• Neural Networks: Groups of neurons connect brain areas and spinal cord.

• Ongoing mapping efforts for the human brain's connectome, revealing neuronal plasticity.

Page 6: Major Parts of a Neuron

• Core components of neurons: Dendrites, soma, and axon.

Page 7: Subdivisions of Neurons

• Three Basic Subdivisions:

  • Dendrites: Gather information meditating input.

  • Soma: Core region integrating information.

  • Axon: Outputs information to other cells.

Page 8: Structure and Function of the Neuron (Part 1)

• Dendritic Spines: Protrusions increasing surface area for contacts with other neurons.

• Axon Hillock: Area where action potential initiation occurs.

Page 9: Structure and Function of the Neuron (Part 2)

• Axon Collaterals: Branches of the axon.

• Telodendria: End branches for signal transmission.

• Terminal Button (End Foot): Knob conveying information to other neurons across the synapse.

Page 10: Information Flow Through a Neuron

• Overview of signal propagation within neurons.

Page 11: Three Functions of Neurons

• Neuronal Types:

  • Sensory Neurons: Relay signals from sensory receptors to spinal cord.

  • Interneurons: Associate sensory and motor activities.

  • Motor Neurons: Transmit signals from brain/spinal cord to muscles.

Page 12: Neuron Shape and Function

• Describes types of neurons:

  • Sensory Neurons: Detect and relay stimulation.

  • Interneurons: Process information and connect to motor neurons.

Page 13: Sensory Neurons

• Types of Sensory Neurons:

  • Bipolar Neuron: A single axon and dendrite relaying visual info.

  • Somatosensory Neuron: Brings body sensory information to the spinal cord.

Page 14: Interneurons (Association Cells)

• Types of Interneurons:

  • Stellate Cells: Small, numerous dendrites in larger brains.

  • Pyramidal Cells: Pyramid-shaped with long axons; convey info within the brain.

  • Purkinje Cells: Highly branched, wide-reaching cells connecting cerebellum and brain/spinal cord.

Page 15: Motor Neurons

• Reside in the lower brain and spinal cord with extensive dendritic networks, facilitating muscle connection.

Page 16: Neuronal Networks

• Flow of information: afferent sensory neurons to interneurons to efferent motor neurons, resulting in behavior.

• Three primary organization aspects: input, association, output.

Page 17: The Language of Neurons: Excitation and Inhibition

• Neurons process thousands of excitatory and inhibitory signals, affecting behavior.

Page 18: Classes of Glial Cells

• Glial Cells: Supportive functions in repair and waste elimination.

• Five classes include ependymal, astrocytes, microglial, oligodendroglial, and Schwann cells.

Page 19: Ependymal Cells

• Function: Produce and secrete cerebrospinal fluid (CSF); involved in hydrocephalus if CSF flow is obstructed.

Page 20: Astrocytes (or Astroglia)

• Functions: Structural support, transport nutrients, enhance brain activity, and promote healing.

• Subject of current research in neuron-to-neuron communication.

Page 21: Blood–Brain Barrier

• Astrocytes facilitate formation and maintenance of the blood-brain barrier; critical for neuron health and repair.

Page 22: Microglia

• Immune cells of the brain; scavenge debris, regulate health, and respond to damage.

Page 23: Oligodendroglia and Schwann Cells

• Myelin: Glial coating around axons; important for efficient neural signal transmission.

• Oligodendrocytes: Myelinate axons in the CNS; Schwann cells do so in the PNS.

Page 24: Detecting Brain Damage

• Overview of methods and implications of assessing neuronal damage.

Page 25: Glial Cells, Disease, and Neuron Repair

• Multiple Sclerosis (MS): Affects myelin, hindering nervous system function.

• Different repair potentials in the CNS vs. PNS.

Page 26: Neuron Repair

• Mechanisms and challenges in neuronal repair post-injury.

Page 27: Internal Structure of a Cell

• Cells: Characterized by proteins and various compounds essential for cellular functions.

Page 28: The Basics Chemistry Review

• Key concepts: Molecules, elements, atoms, ions, and their interactions crucial for cellular function.

Page 29: The Cell as a Factory

• Important terms related to cellular structures related to functions.

Page 30: Cell Membrane: Barrier and Gatekeeper

• Functions of the cell membrane in regulating substance movement and structural components.

Page 31: Bilayer Cell Membrane

• Description of the phospholipid bilayer's structural properties.

Page 32: The Nucleus and Protein Synthesis

• Nucleus: Functions as the cell's executive office; genetic material organization and protein synthesis explanation.

Page 33: Chromosome

• Explanation of chromosome structure and significance in DNA organization.

Page 34: Protein Synthesis

• Overview of processes involved in protein synthesis.

Page 35: The Endoplasmic Reticulum and Protein Manufacture

• Explains the roles of ribosomes and processes involved in translating mRNA into proteins.

Page 36: Protein Synthesis

• Overview and reiteration of the mechanisms in protein synthesis.

Page 37: Transcription and Translation in Protein Synthesis

• Description of the transcription and translation processes critical for synthesizing proteins.

Page 38: Proteins: The Cell’s Product

• Breakdown of amino acids and their structural significance within proteins.

Page 39: Golgi Bodies and Microtubules: Protein Packaging and Shipment

• Functions of Golgi bodies in protein transport and the role of microtubules.

Page 40: Crossing the Cell Membrane: Channels, Gates, and Pumps (Part 1)

• Description of how proteins facilitate substance movement through cell membranes via shape changes.

Page 41: Transmembrane Proteins

• Explanation of various membrane proteins and their functional roles in substance transport.