The Nervous System
“The right half of the brain controls the
left half of the body. This means that
only left handed people are in their
right mind.”
LATERALIZATION OF BRAIN FUNCTION
THE LEFT HEMISPHERE
SPECIALIZES IN LANGUAGE, MATH, LOGIC OPERATIONS, AND THE PROCESSING
OF SERIAL SEQUENCES OF INFORMATION, AND VISUAL AND AUDITORY
DETAILS.
SPECIALIZES IN DETAILED ACTIVITIES REQUIRED FOR MOTOR CONTROL.
THE RIGHT HEMISPHERE
SPECIALIZES IN PATTERN RECOGNITION, SPATIAL RELATIONSHIPS,
NONVERBAL IDEATION, EMOTIONAL PROCESSING, AND THE PARALLEL
PROCESSING OF INFORMATION.
Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings
The Nervous System
A physically connected network of cells,
tissues and organs that allow us to
communicate with and react to the
environment and perform life activities.
FUNCTIONS OF THE NERVOUS
SYSTEM
1. Sensing the World
 vision, hearing, smell, taste,
and touch
2. Transmitting Information
3. Processing Information
4. Producing a Response
The Structural Components of the
NERVOUS SYSTEM

Central Nervous
System (CNS)
Serves as the main
processing center for
the entire nervous
system

Peripheral Nervous
System (PNS)
Made up of all the
nerves that carry
messages to and from
the central nervous
system and other parts
of the body
The Structural Components of the
NERVOUS SYSTEM
Central Nervous System
(CNS)
A. Brain
1. Hindbrain
 Cerebellum
 Brain Stem and Pons
 Medulla Oblongata
2. Midbrain
3. Forebrain
 Cerebrum
 Thalamus
 Hypothalamus
B. Spinal Cord ( Information
Superhighway)
• Smaller part of the brain,
towards the back
• Muscle coordination
is developed here as
well as the memory of
physical skills.
• Helps maintain posture,
muscle control, and
balance (voluntary
movements)
The Cerebellum


If the cerebellum is injured, your movements
become jerky.
When you see an amazing athlete perform, you
are watching a well-trained cerebellum at work.



Attaches to the spinal cord
Made up of the medulla
oblongata, pons and midbrain.
 Medulla oblongata controls
involuntary activities such
as heart rate and
breathing
 Pons and midbrain act as
pathways connecting
various part of the brain
with each other.
Sometimes called the reptilian
brain, because it resembles
the entire brain of a reptile.

Connects the two halves of the
cerebellum.

The bulging center part of the brain
stem

Mostly composed of fiber tracts
Pons
Medulla Oblongata

Composed of nerve tracts to and from
the brain

May be regarded as an extension of the
spinal cord

Almost all of the cranial nerves arise
from this region
Pons and Medulla Oblongata
Contains control centers for
many subconscious and
unconscious functions like:
• Heartbeat and breathing
• Arteriole constriction
• Reflexes (swallowing,
hiccupping, coughing,
sneezing, vomiting)
• Receives signals/information from the Pons and
Medulla Oblongata and forwarded it to the
Forebrain
• Reflex centers for vision and hearing

Receives signals/information
from the different parts of the
body and forwarded it to the
proper regions of the cerebrum.
• Located below the thalamus and maintains
the normal level of different body
conditions.
• Control sensation of feelings of hunger and
taste, body temperature, blood pressure,
hormonal secretion of the pituitary gland.
Large front part of the brain
 Wrinkled with countless
folds and grooves and
covered with an outer
layer of gray matter
called the cerebral cortex.


Divided into 4 lobes
Receives and integrates sensory
signals/information forwarded by the
Thalamus
 Interprets and allows the body to experience
the sensation of taste, touch, smell, seeing,
and hearing
 Responsible for thinking, reasoning, and
imagination
 Controls emotion and memory

Regions of the cerebrum are
specialized for different functions

The
cerebrum is
divided into
frontal,
temporal,
occipital,
and parietal
lobes.
 Extends from the
medulla oblongata to
the region of T12
 Enlargements occur in
the cervical and
lumbar regions
Reflex Arc
“ what happens when you step on a nail”?




Reflexes are automatic
The Stimulus (nail ) is received
by the sensory neurons in the
foot
This info travels to the spine,
where the interneuron is triggered
The interneuron transmits signal
to brain (through the spinal
cord)and carries message back
and stimulates the motor neuron,
to move the foot
The Structural Components of the
NERVOUS SYSTEM
Peripheral Nervous System
(PNS)
A. Somatic PNS
 motor neurons carry
signals from the brain and
spinal cord to voluntary
muscles (conscious control)
The Structural Components of the
NERVOUS SYSTEM
Peripheral Nervous System
(PNS)
B. Autonomic PNS
 motor neurons carry
signals from the brain and
spinal cord to involuntary
muscles (without conscious
control)
1. Sympathetic NS (actions in
emergencies “Fight or flight
response”)
2. Parasympathetic NS ( works
when the body is relaxed )
Spinal Nerves
Figure 7.22a
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings
Slide 7.64
Olfactory
Optic
Oculomotor
Trochlear
Trigeminal
Abducens
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Hypoglossal
Accessory
On Old Olympus Towering Tops A Fat Voracious German Viewed A Hop
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5.
1.
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Olfactory- smell
Optic- vision
Oculomotor- 4 of the 6 extrinsic eye muscles
Trochlear- extrinsic eye muscles
Trigeminal- sensory fibers to the face and motor fibers
to the chewing muscles
Abducens- controls eye muscles that turn the eye laterally
Facial- facial expression
Vestibulocochlear- hearing and balance
Glosopharyngeal- tongue and pharynx
Vagus- parasympathetic control of heart, lungs &
abdominal organs
Accessory- accessory part of vagus nerve, neck & throat
muscles
Hypoglossal- moves muscles under tongue
Classification of Nerve Cells
 Afferent (sensory) nerves – carry
impulses toward the CNS
 Efferent (motor) nerves – carry impulses
away from the CNS
 Mixed nerves – both sensory and motor
fibers
Check this video
Cool Nervous System Facts:
As a fetus in the womb, neurons develop
at the rate of 250,000 per minute.
 We have about 100 billion nerve cells in
our brain by adulthood (over 600 miles
worth) – yet we typically use around 4% at
any given time
 Neurons are our largest cells
 Messages transmit at speeds up of to 180
MPH

REMEDIATION ACTIVITIES
Quarter 3 Module 2: Menstrual and Ovarian Cycle
1.
2.
What’s More pp. 8-9
Post- test pp. 18-19
Deadline of
Submission:
March 8, 2023
Performance Task #2
Deadline : March 11, 2023 at 5PM
Performance Task #2
THANK YOU!