1. The Nervous System

2. Nervous System
The nervous system is made of:
The brain
The spinal cord
The nerves
The senses

3. The Central Nervous System
Brain
Spinal cord

4. The Brain (FYI)
Protected by :
The skull/cranium
Meninges – A membrane that covers the brain and spinal cord

5. Parts of the Brain (FYI)
Cerebrum
Cerebellum
Brain Stem

6. Cerebrum (FYI)
Divided into 4 lobes

7. Cerebrum (FYI)
Frontal: emotion, reasoning, planning, movement, speech, personality
Parietal: touch, pain, taste, pressure, temperature
Temporal: hearing, memory, meaning, language
Occipital: vision

8. Divided into 2 Hemispheres (FYI)
Right Hemisphere
Controls left side of body
Left Hemisphere
Controls right side of body

9. Functions of the Brain Controls voluntary movements
Interprets messages picked up by the senses
Controls Intelligence
Controls Emotion
Regulates physiological functions (hunger, alertness, body
temperature)
Centre of balance and movement coordination
Helps us to do many activities all at once
Controls internal stimuli
Controls involuntary movement

10. The Spinal Cord *Protected by vertebrae* 2 Functions:
Carries nerve impulses
The reflex centre

11. The Spinal Cord What is a reflex?
A rapid involuntary reaction to a stimulus
Quick reaction time in an emergency
Ex: Pulling arm away from sharp object

12. The Spinal Cord Reflex Arc The series of nerve impulses that occur
during a reflex

13. Peripheral Nervous System
Connects body to the CNS.
Made up of all the nerves

14. Peripheral Nervous System
Role:
Transportation of nerve impulses from senses to brain (sensory nerves)
Transportation of nerve impulses from brain to muscles (motor nerves)

15. Staying Sharp! Physical activity
Challenging your brain (mental activities)
Interacting with people (social activities)
Positive thinking (reduce stress factors)
Healthy eating habits (omegas!)
Getting enough sleep!
Avoid drugs...

16. The Neuron
Specialized nerve cells in the nervous system that receive and transmit messages.
FYI: the human body has an average of 100 billion neurons!!!

17. The Neuron Parts of the neuron
Dendrites – receive message
Cell body - contain nucleus
Axon – transmit message
Axon terminals – send message

18. Role of Neurons
To pick up stimuli, transform them into nerve impulses and transmit these

19. Stimulus
A stimulus is a change in the environment.
Example: a hot stove
tripping over a rock

20. Nerve Impulse
An electrical signal transmitted by a neuron

21. Characteristics of the Neuron (FYI)
Can be stimulated – by a stimulus by changing it into nerve impulse
Conductive – transmits nerve impulse from one neuron to another until reaches its target
Consumes a lot of Oxygen and Glucose. Lives only a few minutes without oxygen
Live more than 100 yrs.
Cannot reproduce or be replaced if destroyed

22. Transmission of nerve impulses (FYI)
A nerve impulse travels from neuron to neuron until it reaches its target.
It travels from dendrites to axon terminals

23. Transmission of nerve impulses (FYI)
Nerve impulses travel from one to another by Neurotransmitters (chemical substances) secreted by axon terminals
The transition zone between 2 neurons is called a synapse.

24. Nerve Impulses (FYI)
Nerve impulses move quickly from neuron to neuron and can reach up to speeds of 430km/h.
Making sure there is rapid transmission of information to many parts of body.