WEEK 1 REVIEW

  1. Discuss the neuron doctrine, distinguishing between Golgi's reticular theory and Cajal's neuron doctrine.

    • Golgi's Reticular Theory: Suggested that neurons are a continuous network, connected through cytoplasmic bridges (like a net).

    • Cajal's Neuron Doctrine: Showed that neurons are discrete cells that communicate via contact, not continuity. Cajal used Golgi's stain to prove this, leading to the modern understanding of neurons as individual units.


  2. Key components of a neuron: soma, axon, dendrites.

    • Soma: Contains the nucleus and organelles like the rough ER and mitochondria, crucial for protein synthesis and energy production.

    • Axon: Transmits electrical signals; contains specialized structures like the axon hillock and synaptic vesicles.

    • Dendrites: Receive incoming signals from other neurons.


  3. Neuronal structure and function, focusing on proteins involved in the neural cell body (e.g., rough ER, mitochondria)

    • Rough ER: Produces ion channels and membrane proteins.

    • Mitochondria: Provides energy (ATP) for neuronal functions, including synaptic transmission.


  4. Understand Nissl vs. Golgi stains and their relevance to distinguishing neuronal and glial cells

    • Nissl Stain: Binds to rough ER, highlighting neurons but distinguishing them from glia. Helps study cytoarchitecture.

    • Golgi Stain: Labels entire neurons but only in some cases (unknown why). Used by Golgi and Cajal to study neuron structure.


  5. Differentiate between neuronal cell types and glial cells, including astrocytes, oligodendrocytes, and microglia, and their associated diseases

    • Neurons: Process and transmit information.

    • Glial Cells: Support neurons, divided into:

      • Astrocytes: Provide nutrients (glucose), implicated in ALS and Parkinson’s.

      • Oligodendrocytes: Myelinate CNS neurons, linked to MS, schizophrenia, bipolar disorder.

      • Schwann Cells: Myelinate PNS neurons; allow regeneration.

      • Microglia: Immune response, linked to Alzheimer’s, schizophrenia, autism.


  6. Functions of mitochondria, smooth and rough ER in neurons

    • Mitochondria: Generate ATP, essential for synaptic transmission.

    • Rough ER: Synthesizes membrane proteins and ion channels.

    • Smooth ER: Regulates calcium and lipid synthesis.


  7. Axoplasmic transport: Understand the processes of anterograde and retrograde transport, proteins involved (kinesin, dynein), and ATP's role

    • Anterograde Transport: Kinesin protein moves materials from soma → terminal.

    • Retrograde Transport: Dynein protein moves materials from terminal → soma.

    • ATP: Required for both processes.


  8. Classification of neurons: Based on structure (number of neurites, dendrites) and function

    • By Structure:

      • Unipolar: One process.

      • Bipolar: Two processes.

      • Multipolar: More than two processes.

    • By Function:

      • Sensory Neurons: Detect environmental changes.

      • Motor Neurons: Control movement.

      • Interneurons: Connect neurons within the CNS


  9. Glial cells and associated disorders: Be able to identify characteristics of astrocytes, oligodendrocytes, microglia, and Schwann cells, along with diseases related to them (e.g., MS, ALS)

    • Astrocytes: Provide glucose to neurons; linked to ALS, Parkinson’s.

    • Oligodendrocytes: Myelinate CNS neurons; linked to MS, schizophrenia, bipolar disorder.

    • Schwann Cells: Myelinate PNS neurons; allow nerve regeneration.

    • Microglia: Immune function; linked to Alzheimer’s, schizophrenia, autism.


  10. What is the role of the cytoskeleton in neurons and its involvement in neurodegenerative diseases?

    • Cytoskeleton Components:

      • Microtubules: Transport proteins along the axon.

      • Microfilaments: Support neuronal structure.

      • Neurofilaments: Provide strength and stability.

    • Neurodegenerative Diseases:

      • Tau Proteins stabilize microtubules; their dysfunction is linked to Alzheimer’s Disease (causing transportation failure).


  11. The role of the BBB – blood brain barrier and the consequences of disruption

    • BBB Function: Protects the brain by regulating what enters from the bloodstream.

    • Disruption Consequences: Can lead to infections, inflammation, and neurodegenerative diseases.


  12. What are the factors associated with the RMP- resting membrane potential?

    • Ion Gradients: Na⁺, K⁺, Cl⁻ concentrations inside vs. outside the neuron.

    • Selective Permeability: Neuronal membrane allows some ions to pass but not others.

    • Na⁺/K⁺ Pump: Maintains RMP by pumping 3 Na⁺ out and 2 K⁺ in.


  13. What is the role of the lipid bilayer?

    • Forms a hydrophobic barrier between the inside and outside of the neuron.

    • Regulates ion flow, helping maintain the neuron’s electrical properties.


  14. What is the difference between channels and pumps? We

    • Channels: Allow passive movement of ions down their gradient (no energy needed).I

    • Pumps: Use ATP to actively move ions against their gradient (e.g., Na⁺/K⁺ pump).