Nerve Tissue in Cytology Flashcards
What is nerve tissue?
Nerve tissue is specialised tissue composed of neurons and glial cells that facilitate the reception, transmission, and processing of nerve impulses
What are the three main components of a neuron?
Cell body (Soma): Contains nucleus and organelles
Dendrites: Receive input and increase surface area for connections
Axon: Transmits impulses to other neurons or effectors
Name the four types of glial cells in the central nervous system (CNS)
Astrocytes
Oligodendrocytes
Microglia
Ependymal cells
What is the function of Schwann cells in the peripheral nervous system (PNS)?
Schwann cells form the myelin sheath around axons in the PNS, aiding in faster impulse conduction
What is the structural classification of neurons?
Multipolar neurons (most common)
Bipolar neurons
Unipolar (pseudounipolar) neurons
Anaxonic neurons
What are the two main types of synapses?
Electrical synapse (via gap junctions)
Chemical synapse (via neurotransmitter release)
What is the myelin sheath, and what is its function?
The myelin sheath is a lipid-rich insulating layer that increases the speed of nerve impulse conduction and provides electrical insulation
What is the difference between gray matter and white matter in the CNS?
Gray Matter: Contains neuronal cell bodies, dendrites, and synapses
White Matter: Contains myelinated axons
What are the two divisions of the peripheral nervous system (PNS)?
Somatic Nervous System: Controls voluntary skeletal muscles
Automatic Nervous System: Controls involuntary functions (sympathetic, parasympathetic and enteric divisions)
What are Nissl bodies, and where are they found?
Nissl bodies are aggregates of rough endoplasmic reticulum and ribosomes found in the cell body of neurons
Name two demyelination disorders and their affected systems
Multiple Sclerosis: Affects the CNS
Guillain-Barré syndrome: Affects the PNS
What staining techniques are used in nerve tissue cytology?
Nissl staining (highlights rough ER in neurons)
Silver staining (visualizes axons and synapses)
What are astrocytes, and what is their function?
Astrocytes are glial cells in the CNS that maintain the blood-brain barrier, regulate extracellular ion balance, and provide metabolic support
What is the function of the microglia?
Microglia are phagocytic glial cells in the CNS involved in immune response and debris clearance
What is saltatory conduction?
Saltatory conduction is the rapid transmission of nerve impulses along myelinated axons, where the impulse “jumps” between nodes of Ranvier
