1. Introduction to the Nervous System
The nervous system controls and coordinates functions throughout the body by responding to external and internal stimuli.
Copyright 2012 Dana Kelly

2. New Vocab Words Nervous System Brain Spinal Chord Nerve Neuron
Central Nervous System
Peripheral Nervous System
Sensory neurons
Motor Neurons
Interneurons
Dendrite
Cell Body
Nucleus
Axon
Axon Terminals
Neurotransmitter
Synapse

3. Levels of Organization: The Nervous System
Our bodies are organized into different sized groups:
-CellsTissuesOrgansOrgan SystemsOrganism
(smallest) (largest)
-All organisms are made up of cells.
-The same cell working together make up tissues. Neurons work together to make nervous tissue!
-Groups of tissues make up organs (eye, stomach, brain). Nerves are an organ made up of nervous tissue and other connective tissues.
-An organ system is a group of organs that work together (Nervous system is made up of the brain, spinal chord, and nerves).

4. What is the Nervous System
Brain
Nervous system: The organ system responsible for sending and receiving information in the body
Tells muscles to contract and relax
Time to move
Info from the external environment
“IT SMELLS LIKE DINNER IS READY”
Info from inside the body
“I NEED MORE OXYGEN”
Spinal cord
Nerves

5. 3 Organs OF THE NERVOUS SYSTEM
Brain
1. Brain: The ‘control center’ of the body; controls and interprets all information in the body
2. Spinal cord: major network of nerves in the body; connects to the brain to the rest of the body. The spinal chord is responsible for sending information from the brain to the rest of the body (and vice-versa)
3. Nerve: A group of neurons (and other cell tissues) that carry information from the spinal chord to the rest of the body (and vice-verca)
Spinal cord
Nerves

6. Divisions of the Nervous System
Central Nervous System – consists of the brain and spinal cord.
2. Peripheral Nervous System – Consists of all nerves outside of the brain and spinal cord.

7. The Central Nervous System
The central nervous system is surrounded by meninges – a triple layer of connective tissue – that is “bathed” in a protective fluid called CSF (cerebrospinal fluid). This fluid acts as a shock absorber between the layers and allows for exchange of nutrients.
Copyright 2012 Dana Kelly

8. 1. The Central Nervous System
The Brain:
The brain consists of 4 regions. Each region controls different functions of the brain:
1. Cerebrum
2. Cerebellum
3. Brain Stem
4. Thalamus and Hypothalamus
Copyright 2012 Dana Kelly

9. The Brain The cerebrum is further divided into four lobes or regions:
1. Frontal
2. Temporal
3. Parietal
4. Occipital
Copyright 2012 Dana Kelly

10. The Central Nervous System
The Spinal Column
The spinal column is also known as the vertebral column or the spine.
It consists of 24 bones that are stacked on top of each other like blocks. Each block has a hole in the center that lines up with the blocks above and below it to let the spinal cord pass through. This is called the spinal canal.
Copyright 2012 Dana Kelly

11. The Spinal Cord
Pairs of spinal nerves branch out from the spinal cord by exiting between the vertebrae. They connect the brain to different parts of the body.
Copyright 2012 Dana Kelly

12. The spine contains discs between each vertebrae
The spine contains discs between each vertebrae. They are little cushions that act like shock absorbers. From a side view the spine is curved, which gives it the quality of a spring. From the front or back view, it is straight. If it’s not straight, it’s called a “scoliosis”.
Copyright 2012 Dana Kelly

13. 2. The Peripheral Nervous System
Consists of all nerves outside of the brain and spinal cord. It is divided into two divisions:
1. Sensory Division – Transmits impulses from the sense organs to the CNS.
2. Motor Division – Transmits impulses from the CNS to the muscles.
Copyright 2012 Dana Kelly

14. Motor Division
The Motor Division is further divided into the Somatic Nervous System and the Autonomic Nervous System.
1. Somatic Nervous System – Regulates activities under conscious control, such as muscle movement.
2. Autonomic Nervous System – Regulates activities that are involuntary, such as heart rate, blood flow and movement of food through the digestive tract.
Copyright 2012 Dana Kelly

15. What is a Neuron?
A neuron is the scientific term for a cell found only in the nervous system. The messages carried by the nervous system are called “impulses” which are transmitted by neurons.
Copyright 2012 Dana Kelly

16. What is a synapse?
The space between the dendrites of one neuron and the axon terminals of another is called a synapse. A neurotransmitter is a chemical found in the synapse that helps the message get from one neuron to the other.
Copyright 2012 Dana Kelly