The nervous system controls and coordinates the body's voluntary and involuntary actions and sensations and is divided into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS contains the brain and spinal cord while the PNS contains nerves that connect to the rest of the body. Neurons are the basic working units that transmit electrochemical signals throughout the nervous system, consisting of a cell body, dendrites that receive signals, and an axon that transmits signals. The nervous system works through feedback loops to maintain homeostasis in the body.

1. Presented by Group 1
NERVOUS
SYSTEM AND
HOMEOSTASIS

2. REPORTERS
Jilian Chie Calicdan Ruthlyn Reese Rigor Austine Keanne Pato Ged Ezekiel Duco

3. THE NERVOUS SYSTEM
Is our body's major controlling system.
This is controlled by our brain, which controls our
movements, thoughts, and automatic responses
through a network of nerves and specialized cells
known as neurons.

4. It also controls other body systems and
processes, such as digestion, breathing
and sexual development (puberty). It is
essentially the electrical wiring of the
body. The nervous system is divided into
parts: CNS, PNS and ENS.
NERVOUS SYSTEM

5. HOMEOSTASIS
Is the ability of all living organisms to maintain
internal stability while adjusting to conditions to
survive.
It is the body's attempt to maintain a constant and
balanced internal environment, which requires
constant monitoring and adjustments as
conditions change.
Example: Body temperature control in humans is
one of the most familiar homeostasis.

6. 3 MECHANISMS
1.THE RECEPTOR
detects that something in the
environment is changing.
HOMEOSTATIC REGULATION
refers to the adjustment of systems within the body.
2.THE CONTROL CENTER
a.k.a the integration center, receives
and processes data from the receptor.
3.THE EFFECTOR
responds to control center commands by
either opposing or enhancing the stimulus.

7. HOW IS HOMEOSTASIS
MAINTAINED BY THE BODY?
Homeostasis is maintained by
negative feedback loops. In
contrast, positive feedback loops
push the organism further out of
homeostasis.

8. NEGATIVE FEEDBACK LOOPS
POSITIVE FEEDBACK LOOPS
are characterized by their ability to either
increase or decrease a stimulus, inhibiting
the ability of the stimulus to continue as it
did prior to sensing of the receptor.
are characterized by their
ability to maintain the
direction of a stimulus and
can even accelerate its effect.
(Stimulus is any change in an
organism's environment that
causes the organism to react.)
The term Acclimatization is the
climatic adaptation of an organism
that has been moved to a new
environment

10. The Brain is the central organ of the human
nervous system, and it is joined by the spinal
cord to form the CNS.
It contains up to 100 billion neurons but
weighs only 3 pounds. It is an energy-intensive
organ, accounting for about 2% of a person's
weight but consuming 20% of the body's
energy.
ORGANS OF THE NERVOUS SYSTEM
THE BRAIN

11. What are the parts of the brain?

12. CEREBRUM
is the largest and most complex part
of the brain. It is home to the
information that basically characterizes
us: our intelligence, memory,
personality, emotion, speech, and
ability to move. That information is
processed by specific areas of the
cerebrum and those are the 4 lobes:
the frontal, parietal, temporal, and
occipital lobes.
1.

13. The cerebrum is divided into
right and left halves, known as
hemispheres. They are linked
in the middle by a band of
nerve fibers known as the
corpus callosum, which
allows them to communicate.

14. The cerebral cortex is the
cerebrum's outermost layer (
"gray matter"). The information
gathered by the five senses
enters the brain and is processed
by the cortex. This data is then
routed to other parts of the
nervous system for processing.
Example: When you touch a hot stove, a message is sent not only to
move your hand, but also to another part of the brain to help you
remember not to do it again.

15. CEREBELLUM
(sometimes known as the "small brain")
is positioned in the back of the brain,
beneath the cortex. It is located in the
occipital lobe and is connected to the
brainstem. The cerebellum is
responsible for the following functions:
maintaining balance and posture,
coordinating voluntary movements,
motor learning, and cognitive
functions.
2.

16. BRAINSTEM
It’s a stalk-like part that connects
the cerebrum with the spinal cord,
located at the bottom part of our
brain. Our brainstem sends signals
from our brain to the rest of our
body. It controls many subconscious
body functions, like breathing and
maintaining heart rate.
3.

17. is a long, thin, tubular structure made up
of nervous tissue, which connects your
brain to the lumbar region of the vertebral
column.
Your spinal cord carries nerve signals from
your brain to your body and vice versa.
These nerve signals help you feel sensations
and move your body.
Any damage to your spinal cord can affect
your movement or function.
ORGANS OF THE NERVOUS SYSTEM
THE spinal cord

18. The spinal cord and vertebral
column are frequently referred to as
the spine.
WThe vertebral column is a layer of
bone that covers and protects your
spinal cord. The spinal cord has
three main parts: Cervical (neck).
Thoracic (chest). Lumbar (lower
back).

19. are peripheral nerves composed of nerve
cells that transmit messages between the
spinal cord and the rest of the body,
including muscles, skin, and internal organs.
The spinal nerves have small sensory and
motor branches. Each of the spinal nerves
carries out functions that correspond to a
certain region of the body. These are muscle
movement, sensation, and autonomic
functions (control of internal organs).
ORGANS OF THE NERVOUS SYSTEM
THE spinal nerves

20. In humans there are 31 pairs of
spinal nerves with each pair
connecting to the spinal cord:
8 cervical (upper spine area)
12 thoracic (middle spine area)
5 lumbar (lower spine area)
5 sacral (bottom of the spine)
1 coccygeal (end of the spine)

21. THE PHYSIOLOGICAL
STRUCTURE OF
THE NERVOUS SYSTEM
is divided into three sections: the CNS which is
short for the Central Nervous System it contains the
brain and the spinal cord and the PNS short for
Peripheral Nervous System which consists of the
nerves ganglia and lastly is ENS short for the
Enteric nervous system and is located in the
digestive tract.

22. BRAIN
It is contained within the cranial
cavity of the skull and is
responsible for perception and
processing of sensory stimuli and
the execution of voluntary motor
responses.
It is also responsible for the
regulation of homeostatic
mechanisms which are
secretions of liquids, substances
on the skin.
SPINAL CORD
it is the main pathway for
information connecting the
brain and peripheral nervous
system. The human spinal
cord is protected by the bony
spinal column. The spinal
column is made up of bones
called vertebrae.
CNS

23. are fibers or sensory and motor neurons.
It is a very important part of the nervous
system because it has the biggest priority
of regulating, monitoring and controlling
the functions of the other body system
NERVES
PNS

24. GANGLIA
are clusters of nerve cell bodies found
throughout the body. They are divided into two
broad categories, somatic/sensory ganglia and
the motor/autonomic ganglia
As one nerve enters a ganglion, another nerve
exits it. Ganglia play an essential role in
connecting the parts of the peripheral and central
nervous systems.
It's responsible for reception of sensory stimuli by
the dorsal foot and cranial ganglia

25. ENS or the enteric nervous system. It is
located in the digestive tract and
determines the movements of the
gastrointestinal tract, regulates gastric acid
secretion, changes in local blood flow and
the gut hormones release, and interacts with
the immune system in the gut. This is
responsible for autonomous functions and
can operate independently of the brain and
the spinal cord.
ENS

26. The nervous system is
divided into two main
divisions, the central nervous
system which consists of the
brain and spinal cord and the
peripheral nervous system.
What is CNS and PNS ?

27. PNS CNS
Is the processing center of
the body and consists of the
brain and the spinal cord.
Both of these are protected
by three layers of
membranes known as
meninges.
is the interface between a
human being and its
surroundings. It consists of
tiny white nerves that thread
through every single part of
the body and this includes all
neural structures apart from
the brain and spinal cord.

28. Is the entry point for any stimulus. It also sends
information from receptors to the CNS. A major
component of this is called the somatosensory
system, which comprises all the receptors along the
exterior of our body. This involves special senses
such as vision, hearing, smell, or taste as well as the
sense of touch,pain, and temperature.
The Sensory System

29. the efferent system transmits
information from the CNS out to the
peripheral organs to cause an effect or
action.
The efferent or motor division is
subdivided into the somatic nervous
system and the autonomic nervous
system.
MOTOR /EFFERENT SYSTEM

30. The somatic nervous system or voluntary
nervous system is the part of the
peripheral nervous system associated
with the voluntary control of body
movements via skeletal muscles. The
primary function of the somatic nervous
system is to connect the central nervous
system to the body’s muscles to control
voluntary movements and reflex arcs.
SOMATIC NERVOUS SYSTEM

31. This is a component of the peripheral
nervous system that regulates involuntary
physiologic processes including heart rate,
blood pressure, respiration, digestion, and
sexual arousal.
The autonomic nervous system sends
information from the cns to smooth muscles,
cardiac muscles, and glands. It contains two
anatomically distinct divisions: the
sympathetic and parasympathetic
nervous systems.
AUTONOMIC NERVOUS SYSTEM

32. The sympathetic nervous system
sends signals to all parts of the body
including the skin. It's a division of
the nervous system that functions to
produce localized adjustments such
as sweating as a response to an
increase in temperature and reflex
adjustments of the cardiovascular
system.
The parasympathetic nervous system
predominates in quiet rest and digest
conditions while the sympathetic nervous
system drives the fight or flight response in
stressful situations.
The main purpose of the parasympathetic
nervous system is to conserve energy to be
used later and to regulate bodily functions like
digestion and urination.
Sympathetic and parasympathetic
Nervous System

33. Neuron is a nerve cell that receives and sends
electrical signals over long distances within the body.
It receives electrical input signals from sensory cells
(called sensory neurons) and
from other neurons.
(Sensory Neurons are the nerve
cells that are activated by sensory
input from the environment.)
WHAT IS NEURON?
WHAT IS NEURON?
WHAT IS NEURON?

34. Neurons (also called neurones or nerve
cells) are the fundamental units of the
brain and nervous system, the cells
responsible for receiving sensory input
from the external world, for
sending motor commands to our
muscles, and for transforming and
relaying the electrical
signals at every step in between.
WHAT IS NEURON?

35. It is the creation of new neurons in the
brain, and this can happen even in adults.
Neurogenesis is the process
by which new neurons are
formed in the brain.
WHAT IS NEUROGENOSIS?
WHAT IS NEUROGENOSIS?

36. THREE PARTS OF A NEURON
THREE PARTS OF A NEURON

37. Each neuron in your brain has one long cable that snakes away
from the main part of the cell. This cable, is several times thinner
than a human a hair, is called an axon. Axons are found at the
specialized location on a cell body called axon hillock.
Axon is also called nerve fiber, a portion of a nerve cell (neuron)
that carries nerve impulses away from the cell body. A neuron
typically has one axon that connects it with other neurons or with
muscle or gland cells. Some axons may be quite long, reaching,
for example, from the spinal cord down to a toe.
AXON

38. Dendrites are to receive signals from other
neurons, to process signals, and to transfer
information to the soma of the neuron.
Dendrites also possess organelles that enable
them to alter protein density in response to
changes in frequency of neuronal inputs.
DENDRITES

39. Dendrites are tree-like extensions at the beginning of
the neurons. This allows normal activity in neurons to
be maintained and helps to prevent neurological
disorders such as epilepsy.
dendrites are important for normal neuronal
function and play a vital role in physiological
processes such as memory formation.
DENDRITES

40. It is the nucleus-containing central art of a
neuron exclusive of its axons and dendrites that
is the major structural element of the gray
The Cell Body is also known as soma.
matter of the brain and spinal cord, the ganglia
and the retina.
CELL BODY

41. The job of the cell body is to control all of the functions of
the cell. It contains several important organelles that help it
do this.
Organelles are tiny organs in the cell that each do a specific
job.
The most important organelle in the cell body is the nucleus.
The nucleus contains the cell's DNA and regulates all
processes in the cell. The nucleus also contains the
nucleolus, which makes ribosomes needed for protein
production.
CELL BODY

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