Histology Guide

virtual microscopy laboratory

Chapter 6 - Nervous Tissue

This quiz only covers material that would be expected to be discussed in a histology laboratory.

Objectives

  • Learn how to identify tissues in the nervous system
  • Understand the basic structure of neurons
  • Appreciate differences in the organization of neurons

General Questions

What are the two major types of cells found in nervous tissue? [+]

  • Neurons - structural and functional unit of the nervous system
  • Glial cells (or neuroglial cells) - supporting cells for neurons

Nervous system is divided anatomically into two major components: [+]

  • Central nervous system (CNS) – consists of the brain and spinal cord
  • Peripheral nervous system (PNS) – all nervous tissue outside the CNS

What are the three major parts of a neuron and their functions: [+]

  • Cell body (or perikaryon, soma) – processes and integrates signals from dendrites
  • Dendrites – branched processes that receive stimuli and conduct impulses toward the cell body
  • Axon – single axon that conducts nerve impulses to other cells through synapses

Neurons are classified into three types based on the structure of their processes: [+]

  • Bipolar - found in special sensory organs, like olfactory and vision
  • Pseudounipolar (or unipolar) - sensory neurons found in dorsal root (or spinal) ganglia
  • Multipolar - most common type of neuron

What are the four types of glial cells in the CNS and their major functions: [+]

  • Astrocytes – many roles in support and nourishment of neurons
  • Oligodendrocytes – insulate axons and form myelin sheaths around more than axon
  • Microglia – specialized macrophages
  • Ependymal cells – line the ventricles in the brain and the central canal of the spinal cord - produce and circulate cerebrospinal fluid

Microscope Slides

Part 1

Part 2

What is a cluster of nerve cell bodies outside the CNS called? [+]

Peripheral ganglia

What is another name for neurons with cell bodies in ganglia? [+]

Ganglion cells

What are the two types of glial cells in the PNS and their major functions: [+]

  • Schwann cells – structure depends whether the axons are non-myelinated/myelinated
    • Wrap multiple, non-myelinated axons in cytoplasmic folds
    • Wrap a single, myelinated axon within a myelin sheath
  • Satellite (or capsule) cells – cells that support neurons in ganglia

Part 3

What are the two subdivisions of the autonomic nervous system? [+]

  • Sympathetic nervous system – involved in functions requiring quick responses (i.e., stress, impending danger, and "fight or flight" response)
  • Parasympathetic nervous system – regulates functions of body organs, blood vessels, and smooth muscle (i.e., "rest and digest" response)

How can you distinguish sympathetic ganglia from parasympathetic ganglia? [+]

Parasympathetic ganglia are nearby/within the organ they innervate

Part 4

What are bundles of axons that extend from the CNS into the PNS called? [+]

Peripheral nerves