Chapter 49: The nervous system - PowerPoint PPT Presentation


PPT – Chapter 49: The nervous system PowerPoint presentation | free to download - id: 6a8f11-MjA4N


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation

Chapter 49: The nervous system


chapter 49: the nervous system by; kelly wacker, jenna felix, vanesa abad – PowerPoint PPT presentation

Number of Views:38
Avg rating:3.0/5.0
Slides: 24
Provided by: CUSD95
Learn more at:


Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Chapter 49: The nervous system

Chapter 49 The nervous system
  • By Kelly Wacker, Jenna Felix, Vanesa Abad

History And Habitat (1)
  • The simplest organisms, the cnidarians, have only
    a simple nerve net.
  • Because of their habitat, the ocean, there was no
    need for a more complex nervous system.
  • Nerve Net a series of interconnected nerve cells
  • As the earth evolved, more complex creatures
    became more complex with their nervous system
    like the star fish.
  • The star fish has organized its nerves into a
    nerve ring where its mouth is but has also has
    evolved to have radial nerves extending to all of
    its appendages.
  • Nerves The axons of multiple nerve cells that
    are often bundled together.
  • The most complex creatures are normally animals
    that are bilateral. They show signs of
    cephalization and also ganglia. These animals had
    to change to survive better on land.

How the nervous system Evolved (1)
Radial nerve
Nerve cords
Ventral nerve cord
Nerve ring
Transverse nerve
Nerve net
Segmental ganglia
(a) Hydra (cnidarian)
(b) Sea star (echinoderm)
(d) Leech (annelid)
(c) Planarian (flatworm)
Anterior nerve ring
Spinal cord (dorsal nerve cord)
Ventral nerve cord
Sensory ganglia
Longitudinal nerve cords
Segmental ganglia
(e) Insect (arthropod)
(h) Salamander (vertebrate)
(f) Chiton (mollusc)
(g) Squid (mollusc)
The central nervous system (2)
  • The central nervous system is composed of only
    the brain and the spinal cord they are extremely
    in sync with one another.
  • The brain provides the power behind the behavior
    of vertebrates.
  • The spinal chord conveys information to and from
    the brain and makes basic patterns of locomotion.
  • But the spinal cord can also act independently of
    the brain.

Peripheral nervous system (PNS)
Central nervous system (CNS)
Cranial nerves
Ganglia outside CNS
Spinal cord
Spinal nerves
The peripheral nervous system(2)
https// Divisi
on of the nervous system
  • The peripheral nervous system consists of the
    cranial nerves, the ganglia outside the CNS, and
    the spinal nerves.
  • It is then divided into the efferent neurons and
    the afferent neurons.
  • The afferent neurons are the sensory neurons
  • The efferent neurons which are then broken up
    into two categories as well, the motor system and
    the autonomic nervous system.
  • The motor system is for locomotion.
  • The autonomic nervous system is then broken up
    into three parts.
  • There is the sympathetic division which
    corresponds to arousal and energy generation .
  • The parasympathetic division which generally
    causes calming and a return to self-maintenance
  • Last there is the enteric division which consists
    of networks of neurons in the digestive tract,
    pancreas, and gallbladder.

Reflex Movement (3)
  • Reflex an automatic response to a stimuli
  • Reflexes are used to protect the body by
    producing a rapid response to a stimuli
  • The spinal cord uses neurons to transmit signals
    to a certain body parts to produce a reflex
  • Sensory Neurons Sends information to the spinal
  • Motor Neurons Sends Signal to the muscle
  • Interneurons Inhibits motor neurons that lead to
    a different muscle (hamstring)

Parts of the brain (4)
  • In vertebrates, the spinal cord and the brain
    came from the dorsal embryonic nerve cord.
  • A dorsal embryonic nerve cord also hollow
  • During development the embryonic nerve cord
    changes into the central canal of the spinal cord
    as well as the ventricles of the brain.
  • Both the four ventricles and the central canal
    are filled with cerebrospinal fluid.
  • The cerebrospinal fluid is formed by the
    filtration of arterial blood that is in the
  • This fluid slowly circulates through both parts
    that we have talked about, this fluid then drains
    into the veins, which supplies different parts of
    the brain with different nutrients and hormones,
    but it also takes waste away from the brain.
  • The fluid in mammals also cushions the brain and
    the spinal cord because it circulates between
    layers of connective tissue.

Gray Vs. white matter (4)
  • Both gray and white matter are found in the brain
    and the spinal cord.
  • Gray Matter consists mainly of neuron cell
    bodies, dendrites, and unmyelinated axons.
  • Located on the outer rim of the brain and in the
    inner portion of the spinal cord.
  • White Matter consists of bundled axons that have
    myelin sheaths, these give the axons a whitish
  • Located in the inner portion in the brain and
    outer portion in the spinal cord.

Comprehension Check
  • 1. What part of the brain takes away the waste
    that is produced in the brain?
  • Ventricles
  • Gray Matter
  • D. Central Canal
  • Cerebral
  • Spinal Fluid

Glia (5)
  • Types of Glia
  • Ependymal cells contain cilia that promotes the
    circulation of the cerebrospinal fluid
  • Astrocytes Provide structural support for
    neurons. Regulates the extracellular
    concentrations of neurotransmitters and ions.
    (act as stem cells)
  • Microglia protects the nervous system from

Glia (5)
  • Types of Glia cont.
  • Oligodendrocytes functions in axon myelination
  • Schwann Cells same as oligodendrocytes but the
    function occurs in the PNS
  • Radial Glia (act as stem cells) plays an
    important role in the development of the nervous

Autonomic Nervous System (6)
  • Function Regulates the internal environment by
    controlling the smooth and cardiac muscles and
    the organs of the digestive, cardiovascular,
    excretory, and endocrine system
  • Involuntary Actions
  • 3 Divisions
  • Sympathetic
  • Parasympathetic
  • Enteric

Sympathetic Division (6)
  • Corresponds to
  • arousal and energy
  • generation. Prepares
  • the body for quick
  • action in emergencies
  • Ex. Fight or flight,
  • increased heart
  • rate, increased
  • breathing rate

Parasympathetic Division (6)
  • Actions promote calming and conserves bodily
  • Ex. Decreased heart rate, digestion

Enteric Division (6)
  • Network of neurons in the digestive tract,
    pancreas, and gallbladder.
  • neurons of the enteric division control secretion
    in organs and control the muscles that produce
  • Regulated by the sympathetic and parasympathetic

Comprehension check
  1. Afferent Neurons
  2. Motor System
  3. Sympathetic Division
  4. Parasympathetic Division
  5. Enteric Division

A. Fast pumping heart
D. Heavy breathing (Like when you are going to
Comprehension Check
  • Label the correct division of the autonomic
    nervous system. (S) for sympathetic, (P) for
    parasympathetic, and (E) for enteric
  • 1. When activated, blood pressure and heart rate
    increase __
  • 2. Controlled by the other two branches of the
    system __
  • 3. When activated, digestion continues at a
    normal rate __

Structure Of the brain (7)
  • In early stages of development there are three
    sections of the
  • brain the forebrain, the midbrain, and the
  • Forebrain develops into the cerebrum, the
    thalamus, the hypothalamus, and the epithalamus.
  • Cerebrum largest part of the brain, that has
    high brain function
  • Thalamus involved in sensory perception and
    regulation of motor functions
  • Epithalamus secretion of melatonin by the
    pineal gland
  • Hypothalamus connects the nervous system to the
    endocrine system with the pituitary gland
  • Midbrain the section of the brain that develops
    into the brain stem
  • The hindbrain develops into the pons, cerebellum,
    and medulla oblongata.
  • Medulla Oblongata deals with autonomic
    functions, like breathing, heart rate and blood
  • Pons carries conduct signals from the cerebrum
    to the cerebellum and medulla, and carry the
    sensory signals up into the thalamus
  • Cerebellum plays a role in motor control and it
    is involved in some cognitive functions like
    attention and language, and it regulates fear and
    pleasure responses

Reticular System (8)
  • A diffuse network of neurons in the core of the
  • Function Acts as a sensory filter
  • Determines which incoming information reaches the
    cerebral cortex
  • The more information the cortex receives, the
    more alert/awake a person is

Left and Right cerebral hemisphere (9)
  • Both hemispheres contain
  • Outer covering of gray matter
  • Cerebral cortex
  • Basal nuclei (important for learning and planning
    movement orders)
  • Internal white matter

Left and right Cerebral hemispheres (9)
  • The left cerebral cortex controls the movement of
    the right side of the body. Also receiving
    information from the right side of the body
  • The right cerebral cortex controls the movement
    of the left side of the body. Also receiving
    information from the left side of the body
  • Right Hemisphere main functions
  • Visual images, music, and facial recognition
  • Left Hemisphere main functions
  • Language, Math, and Logic

Brocas Area
Wernicke's Area
Functions of the brain regions (10)
  • There are four sections of the brain the Frontal
    lobe, Parietal lobe, Temporal lobe, and the
    Occipital lobe.
  • The frontal lobe helps plan actions and
    movement. There is also the frontal association
    area that helps with speech. When you are using
    language you use both your frontal lobe and your
    temporal lobe. They work together simultaneously.
    Also it helps us with short term memory and
  • The Parietal lobe receives somatosensory
    information, and also taste information.
  • The Temporal lobe receives auditory information
    and amygdala, which is located in the temporal
    lobe, lets us feel emotions and helps our memory.
  • The Occipital lobe receives visual information.

Corpus Collosum (11)
  • A broad transverse nerve tract connecting the two
    cerebral hemispheres
  • If severed, the two hemispheres cannot
  • http//