1. 5 Main Sensory Organs
S.O
Skin
Nose
Tongue
Ear
Eye

2. The function of the sensory organ
Detect stimuli or changes in the environment
Pass the impulse to the brain for interpretation then followed by action (respond) if necessary.
Provide the ability to protects us from harm or injury
What if without sensory organ??

3. The function of 5 S.O Sensory Organ Stimuli Detected Main Function
Skin
Touch, pressure, pain, heat, cold
Organ for touch
Nose
Chemicals
Organ for smell
Tongue
Organ for taste
Ear
Sound
Organ for hearing
Eye
Light
Organ for sight

4. The Human Nervous System
Central N.S
Brain
Spinal Cord
Nerves
Sensory Nerves
Motor Nerves

5. Function of nervous system
Detecting stimuli and changes in environment
Send the information (in the form of nervous impulse) to the brain for interpretation,
The brain sends out instruction (in the form of nervous impulse) to the relevant parts of the body for action to be taken.

6. Components of nervous system
Brain
Spinal cord
Nerves

7. Central Nervous System

8. Nerves

9. The Pathway From Stimulus To Respond
Sensory organ
Sensory nerves
Brain
Motor Nerves
Response

10. Idea through diagram

11. The Sense of Touch The skin made up of 2 layers: Epidermis and Dermis
Epidermis : very thin layer of dead cells which protects the surface of the body
Dermis : Consisting the structure such as living cells, blood capillaries, swear glands, nerves, nerve endings (receptors).

12. Structure of Human skin and Receptors in Human Skin

13. Type of receptors and Functions
Touch receptors
Detects any contact made with the skin
Pressure receptor
Detects pressure exerted on the skin
Pain receptor
Detects pain when the skin is injured
Heat receptor
Detects heat or any rise in temperature
Cold receptor
Detects a cold substance or any fall in temperature

14. Sensitivity The receptors are not evenly distributed in the skin.
This (uneven distribution of receptors) make some parts of the body more sensitive than other parts.
Factors of sensitivity:
The thickness of the epidermis
The concentration of receptors

15. Activities What is a sensory organ?
Which of our senses are known as chemical senses?
Which parts of the body form the central nervous system?
Where is the spinal cord situated?
Name a receptor which is found in the epidermis.
What is the function of the epidermis of the skin?
What is the function of the skin as a sensory organ?

16. Answer
A sensory organ is one which detects stimuli and changes in the surrounding
Sense of taste and sense of smell
The brain and the spinal cord
Within the backbone
Receptor for pain
To protect the skin
To detect stimuli from the surrounding