Flashcards in Chapter 1 - Studying the Nervous System Deck (27):
What are gap junctions, and why would Camillo Golgi care about them?
Gap junctions are the rare intercellular continuities between some neurons, these neurons do not communicate through with each other through neurotransmitters, but instead allow the current flow to diffuse through the gap junction and continue in the neighboring cell. Camilio Golgi was an Italian pathologist who championed a "retikular theory" of nerve cell communication, of which nerve cells communicate because they are connected through protoplasmic links.
The cells of the nervous system can broadly be divided into two types. Which?
Neurons and Glia.
The number of inputs to a single neuron.
The number of targets innervated by any one neuron.
What is another word for dendritic branches?
Divide neurons into two types based on their length and function.
Short interneurons and projection neurons.
Which four types of glial cells are there?
Astrocytes, oligodendrocytes , microglial cells and glial stem cells.
What are the functions of astrocytes?
Cells that maintain the chemical environment, and have stem cell properties.
What are the functions of oligodendrocytes?
They are responsible for the myelination of the CNS axons. They also have stem cell properties.
What are the functions of microglial cells?
They share properties with macrophages found in other tissues. They remove cellular debris from sites of injury or normal cells turnover. They also secrete signaling molecules that modulate local inflammation and influence cell survival or death.
What are the functions of glial stem cells?
Can generate additional precursors or differentiated glia, and in some cases: neurons.
Where in the brain can you find glial stem cells?
Astrocytes in the subventricular zone, and oligodendroglial precursors scattered throughout the white matter.
What is the neuropil?
The region between nerve cell bodies.
Neurons carrying information from the periphery to the brain are called...
Neurons carrying information from the brain to the periphery are called...
What is another name for the "knee-jerk" reflex?
The myotatic reflex.
Explain how the myotatic reflex works. You need to mention the following: the muscles involved, and be able to draw the neurons involved and how they are connected.
Score yourself according to the picture on p. 12
What is meant by a neurons receptive field?
The region in sensory space (e.g. the body surface) within which a specific stimulus elicits action potential response.
The peripheral nervous system (PNS) consist of sensory and motor components. The motor components can be divided into two parts. Which?
1. Somatic motor system
2. Visceral motor system/Autonomic motor divison.
What is the somatic motor system?
The motor axons that connect the brain and spinal cord to skeletal muscles make up the somatic motor division. This includes the cranial nerves and the spinal nerves.
What is the visceral motor system?
The cells and axons that innervate smooth muscles, cardiac muscle, and glands make up the visceral or autonomic motor division.
The autonomic division of the PNS can be further divided into..
1. The sympathetic division
2. The parasympathetic division
3. The enteric system
What is the sympathetic division of the autonomic nervous system?
The sympathetic division of the autonomic nervous system has ganglia that lie along or in front of the vertebral column and send their axons to a variety of peripheral targets.
What is the parasympathetic division of the autonomic nervous system?
The parasympathetic division has ganglia that are found within or adjacent to the organs they innervate.
What is the enteric division of the autonomic nervous system?
It is made up of small ganglia as well as individual neurons scattered throughout the wall of the gut. These neurons influence gastric motility and secretion.
Where do we find the neurons that originate the parasympathetic component of the autonomic nervous system?
The neurons that originate the parasympathetic component are found in the spinal cord and brainstem. Specifically cranial nerves C, IC, VII, III and sacral spinal nerves.