Science-Reviewer-3rd-Quarter-for--biology

Science Reviewer 3rd Quarter


LESSON 1: NERVOUS SYSTEM Parts of the CNS

NERVOUS SYSTEM A. BRAIN

- The nervous system receives and • comprised of billions of
Relays information about activities interconnected neurons and
within the body and monitors and glia
responds to Internal and External
Changes.




Functions of the 2 Halves of the Cerebrum
Neurons
- specialized cells that carry messages
throughout the nervous system
- It is the basic functioning unit of the
Nervous System


4 FUNCTIONS:

 Sensory Function - Gathers information
both from the outside world and from
inside the body.
 Transmits the information to the
processing area of the brain and spinal
cord.
 Integrative Function - Processes the
information to determine the best Division of the Brain
response
 Motor Function - Sends information to
muscles, glands, and organs so they can
respond correctly. Muscular contraction
or glandular secretions.


2 MAJOR DIVISIONS
1. THE CENTRAL NERVOUS SYSTEM (CNS)
- Relays messages, processes
information, and compares and 1. Forebrain
analyzes information  Telencephalon (Cerebrum)
- It consist of the brain and the spinal - Conscious thought processes,
cord intellectual functions

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- Conscious and Subconscious Functions of the Different Parts of the
regulation of skeletal muscle Brain
contraction.
 Diencephalon
Thalamus – relay and proce-
ssing centers for sensory
information.

Hypothalamus – Centers
controlling emotions, auto-
nomic functions, and horm-
one production.
2. Midbrain

 Mesencephalon (Midbrain)
Lobes of the Brain
- Processing of Visual and
Auditory data.
- Generation of reflexive soma-
tic motor responses.
3. Hindbrain

 Metencephalon
(Cerebellum)
- Coordinates complex somatic
motor patterns
- Adjust output of other
somatic motor centers in the
brain and spinal cord. B. SPINAL CORD
(Pons)
- Relays sensory information to
cerebellum and thalamus
- Subconscious Somatic and
Visceral motor centers.
 Myelencephalon (Medulla
Oblongata)
- Relays sensory information to
thalamus
- Autonomic centers for
regulation of visceral func-
tions such as cardiovascular,
respiratory, etc.

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2. PERIPHERAL NERVOUS SYSTEM TYPES OF NEURONS
- connects the central nervous system to 1. Sensory Neuron
the organs and other body parts
 Receptor
Subdivisions  bring messages to CNS
 afferent neuron
a) Sensory Division - carries info to the
brain and spinal cord. 2. Motor Neuron
b) Motor Division - carries info from the
 Carry impulses from the brain and spinal
brain to the bodies effectors (things that
cord to MUSCLES or GLANDS.
do the work)
 Muscles contract
 Somatic nerves relay commands to  Glands secrete
and from skeletal muscle (VOLUNT-  efferent neuron
ARY CONTROL) 3. Interneuron
Parts:
1. Spinal Nerves  spinal cord and  Connects sensory & motor neurons
body  Found entirely within the Central
2. Cranial Nerves  brain stem Nervous System


 Autonomic nerves send signals to
and from smooth muscles
(INVOLUNTARY CONTROL)
Subdivision:
1. Sympathetic  under stress
2. Parasympathetic return to no-
rmal or relaxed mode




PARTS OF A NEURON

 Dendrites
- Receive stimulus and carries impulses
toward the cell body

 Cell Body
- Contains nucleus & most of cytoplasm
- Performs most of the metabolic activity
of the cell, including the generation of
LESSON 2: NEURONS
ATP and synthesis of protein
NEURON  Axon
- Basic functional cell of nervous system
- Fiber which carries impulses away from
- Messages take the form of electrical
the cell body
signals, and are known as IMPULSES.
- A Neuron carries impulses in only ONE - Ends in a series of small swellings called
direction. axon terminals