What is different about activities on the two
sides of the synapse (axon next to muscle or
dendrite of other nerve)?
SALMAN UL ISLAM
2013298039
31.03.2014
Contents
o Introduction
o Nerve Cell
o Synapse
o Transmission across the synapse----- Neuromuscular
junction (NMJ)
o Summary
Introduction
o Neuron-----electrically excitable cell-----processing and
transmitting information through electrical and chemical
signals.
o Neurons communicate with each other by synaptic
transmission.
o Synapses transmit, process, and store information in
brain.
Courtesy of the Südhof lab. See Südhof, T.C. 2008. Nature 455:903-911 for details.
NERVE CELL
Three parts of a nerve cell are:
o dendrites: branches that receive sensory input and
bring it to the neuron’s cell body;
o cell body: contains the nucleus, mitochondria, and
ribosomes. The cell body carries on the normal metabolic
cellular functions of the nerve cell.
o axon: a long fiber extending from the cell body. The role
of the axon is to transmit a nerve impulse to another cell.
http://highered.mcgraw-hill.com/sites/dl/free/0073403474/858357/answers2e_ch25.doc.
Parts of a Nerve cell
http://cnx.org/content/m44731/latest/?collection=col11448/latest
SYNAPSE
SYNAPSE
 The presynaptic cell ends in an axon terminal that contains
calcium channels and synaptic vesicles with
neurotransmitters.
 The postsynaptic cell has ion channels with receptors for
the neurotransmitters.
 Between the two cells is a small gap called the synaptic
cleft.
http://highered.mcgraw-hill.com/sites/dl/free/0073403474/858357/answers2e_ch25.doc.
Transmission across the synapse-----
Neuromuscular junction (NMJ)
o “ The place where the motor neuron makes a functional
contact with the skeletal muscle cell is called
NEUROMUSCULAR JUNCTION or MYONEURAL
JUNCTION”
Neuromuscular Junction
What is the
mechanism of
Neuromuscular
Transmission
Myasthenia Gravis, A Seminar Report Posted: September 21, 2010 in Physiology, Toxic Med
From LIFE: The Science of Biology (Sadava et al., 2010)
Fate of Acetylcholine
Summary
 The synapse is a connection between a neuron and its
target cell (which is not necessarily a neuron).
 The presynaptic element is the synaptic end bulb of the
axon where Ca2+ enters the bulb to cause vesicle fusion
and neurotransmitter release.
 The neurotransmitter diffuses across the synaptic cleft to
bind to its receptor.
 Resulting action potential leads to muscle contraction.
 The neurotransmitter is cleared from the synapse either
by enzymatic degradation or neuronal reuptake.
What is different about activities on the two sides of the synapse?

What is different about activities on the two sides of the synapse?

  • 1.
    What is differentabout activities on the two sides of the synapse (axon next to muscle or dendrite of other nerve)? SALMAN UL ISLAM 2013298039 31.03.2014
  • 2.
    Contents o Introduction o NerveCell o Synapse o Transmission across the synapse----- Neuromuscular junction (NMJ) o Summary
  • 3.
    Introduction o Neuron-----electrically excitablecell-----processing and transmitting information through electrical and chemical signals. o Neurons communicate with each other by synaptic transmission. o Synapses transmit, process, and store information in brain. Courtesy of the Südhof lab. See Südhof, T.C. 2008. Nature 455:903-911 for details.
  • 4.
    NERVE CELL Three partsof a nerve cell are: o dendrites: branches that receive sensory input and bring it to the neuron’s cell body; o cell body: contains the nucleus, mitochondria, and ribosomes. The cell body carries on the normal metabolic cellular functions of the nerve cell. o axon: a long fiber extending from the cell body. The role of the axon is to transmit a nerve impulse to another cell. http://highered.mcgraw-hill.com/sites/dl/free/0073403474/858357/answers2e_ch25.doc.
  • 5.
    Parts of aNerve cell http://cnx.org/content/m44731/latest/?collection=col11448/latest
  • 6.
  • 7.
    SYNAPSE  The presynapticcell ends in an axon terminal that contains calcium channels and synaptic vesicles with neurotransmitters.  The postsynaptic cell has ion channels with receptors for the neurotransmitters.  Between the two cells is a small gap called the synaptic cleft. http://highered.mcgraw-hill.com/sites/dl/free/0073403474/858357/answers2e_ch25.doc.
  • 9.
    Transmission across thesynapse----- Neuromuscular junction (NMJ) o “ The place where the motor neuron makes a functional contact with the skeletal muscle cell is called NEUROMUSCULAR JUNCTION or MYONEURAL JUNCTION”
  • 10.
  • 11.
    What is the mechanismof Neuromuscular Transmission
  • 12.
    Myasthenia Gravis, ASeminar Report Posted: September 21, 2010 in Physiology, Toxic Med
  • 13.
    From LIFE: TheScience of Biology (Sadava et al., 2010)
  • 14.
  • 15.
    Summary  The synapseis a connection between a neuron and its target cell (which is not necessarily a neuron).  The presynaptic element is the synaptic end bulb of the axon where Ca2+ enters the bulb to cause vesicle fusion and neurotransmitter release.  The neurotransmitter diffuses across the synaptic cleft to bind to its receptor.  Resulting action potential leads to muscle contraction.  The neurotransmitter is cleared from the synapse either by enzymatic degradation or neuronal reuptake.