- Fact 2 - The Nervous System has 2
parts: The "central" nervous system and the "peripheral" nervous
system
- Fact 3 - The "central" nervous
system is comprised of the
brain, retina and spinal cord
- Fact 4 - The "peripheral" nervous
system is the nerve tissue that transmits sensation and motor
information back and forth from the body to the central nervous
system
- Fact 5 - The nervous system is
primarily made up of two categories of cells: neurons and glial
cells
- Fact 6 - Neurons: Neurons send
signals to other cells as electrochemical waves travelling along
thin fibers called axons
- Axons: Axons cause chemicals,
called neurotransmitters, to be released at junctions which are
called synapses
- Fact 7 - Ganglia: Clusters of
neurons called ganglia which provide relay points and
intermediary connections between the peripheral and central
nervous systems
- Fact 8 - Glial Cells: the nervous
system contains specialized cells called glial cells, or glia,
which provide structural and metabolic support
- Fact 9 - There are multiple ways
that a cell can send signals to other cells
- Fact 10 - There are multiple ways
that a cell can send signals to other cells
- Fact 11 - Hormones: Hormones
release chemicals called into the internal circulation
- Fact 12 - The nervous system can
malfunction in a wide variety of ways, due to:
- physical damage due to trauma
- physical damage due to poison
- infection
- genetic defects
- aging
- Fact 13 - The smooth functioning of
the 5 senses of touch, sight, taste, hearing and smell, is
attributed to the nervous system
- Fact 14 - The human brain consists
of approx 100 billion neurons
- Fact 15 - In humans, the right side
of the brain controls the left side of the body, whilst the left
side of the brain controls the right side of he body
- Fact 16 - A man's spinal cord is a
bundle of nerve tissue that is about 17.7 inches long, an
average woman's spinal chord is 16.9 inches long
- Fact 17 - The brain weighs
approximately 3lbs
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