Transcript THE NERVOUS SYSTEM - Coastal Bend College

THE NERVOUS SYSTEM
CHAPTER 10
MEDICAL TERMINOLOGY
FUNCTION OF THE NERVOUS
SYSTEM
Have you ever wondered what causes your
body to do the things it does?
 Control of the body’s billions of cells is
accomplished by
 the
nervous system
 the endocrine system

Parts of the nervous system communicate
information to body structures
ORGANS OF THE NERVOUS SYSTEM
 BRAIN
 SPINAL CORD
 NERVES
OF THE BODY
Let’s examine each of these
in detail
NERVES
Nerves are a combination of cells
 Nerves are a group of impulse carrying
fibers that connect the brain and spinal cord
with other parts of the body
 Other terms associated with nerves are:
A Ganglion
A Plexus
Receptors

NEURONS
What is a neuron?
 Neurons are the basic cells of the nervous
system
 Each neuron consists of 3 parts
CELL BODY
DENDRITES
AXON
Jugular vein
DENDRITES/AXONS
DENDRITES
 Branch like
projections off the
cell body
 Receive impulses
and conduct the
impulses to the cell
body
DENDRITES/AXONS
DENDRITES
 Branch like
projections off the
cell body
 Receive impulses
and conduct the
impulses to the cell
body
AXONS



Axons look like
elongated projections
Axons transmit
impulses away from
the cell body
Groups of wrapped
axons are fascicles
NEURONS
There are 3 types of neurons
according to the direction in which
they transmit impulses
 SENSORY NEURONS
 MOTOR NEURONS
 INTERNEURONS
NEUROTRANSMITTERS
What are neurotransmitters?
 Chemicals by which
neurons communicate.
 This chemical substance
helps impulses jump
across the synapse so the
impulse can continue
along its pathway or
reflex arc
NEUROGLIA



Neuroglia are
supportive and
connective cells
They do not transmit
impulses
They hold the
functioning neurons
together
DIVISIONS OF THE NERVOUS
SYSTEM
The nervous system is divided into 3
parts:
 Central Nervous System
 Peripheral Nervous System
 Autonomic Nervous System
Let’s examine each of these systems
CENTRAL NERVOUS SYSTEM
The Central
Nervous System
consists of:
 Brain
 Spinal Cord
THE BRAIN
DIVISIONS OF THE BRAIN
 Brain Stem
Medulla Oblongata
Pons
Midbrain
 Cerebellum
 Diencephalon
 Cerebrum
THE BRAIN STEM
Medulla oblongata is located at the lowest
part of the brain and consists of gray and
white matter
 Pons consists of gray and white matter and
is situated at the base of the brain where the
nerve cells cross from one side of the brain
to control the opposite side of the body
 Midbrain consists of gray and white matter

THE BRAIN AND ITS PARTS
Cerebellum the
2nd largest part of
the brain
 Cerebrum the
largest and
uppermost part of
the brain. It’s
divided into 4 lobes

DIENCEPHALON
The diencephalon
is a small part of
the brain and
consists of:
 Hypothalamus
 Thalamus

THE SPINAL CORD
The main function of the
spinal cord is to carry nerve
impulses that affect the limbs
and lower parts of the body
 Both the brain and spinal cord
are protected by the meninges
and cerebrospinal fluid

MENINGES & FLUID
The meninges consists of 3 layers of tissue
The Dura Mater
The Arachnoid Membrane
The Pia Mater
 Cerebrospinal Fluid is a clear, colorless
fluid that flows throughout the brain and
around the spinal cord and helps to cushion
these organs

PERIPHERAL NERVOUS
SYSTEM
Consists of:
Crainal Nerves
Spinal Nerves
 There are 12 pairs of crainal nerves
 There are 31 pairs of spinal nerves and they
are names after the artery they accompany
or the body part they innervate

AUTONOMIC NERVOUS
SYSTEM
 The
autonomic nervous system
consists of motor neurons. There are 2
divisions of the autonomic nervous
system
 Sympathetic Nervous System
 Parasympathetic Nervous System