1. Chapter 1

2. FeelsmellTasteSeeHear What are senses?

3. 1.1 Sensory Organs To detect the surroundings changes. Sensory organ very sensitive to stimuli. Sensory organstimulus eyelight EarSound NoseChemical vapour (smell) SkinTouch, pressure, pain, heat, cold tongueChemical substances (taste)

4. !!Stimulus detected!! Stimulus Receptors in sensory organs Nerve impulse nerves Brain Effectors( muscles, glands) Response Nerve impulse nerves Nerve impulse

5. 1.2 Sense of touch

6. Heat receptorsPain receptors Cold receptors Touch receptors Pressure receptors Epidermis Dermis

7. touch receptors- help us feel slight touch pain receptors - help us feel pain heat receptors - help us feel heat cold receptors - help us feel cold

8. Epidermis - The epidermis is the outer layer of the skin, the epidermis itself is divided into three layers - The outer most layer of the epidermis is the dead cell The epidermis is a tough and water resistance layer that limits water loss - Epidermis also protects the sensitive cells under it and prevents the entry of germs into your body Dermis - The dermis is the inner layer of your skin -There are glands, receptors and blood vessel in the dermis - There are two glands in the dermis, which are sweat gland and sebaceous gland - There are five receptors in the dermis, which are pain, pressure, heat, cold and touch receptors.

9. Skin is the sensory organ of touch Respond to heat, cold, pressure, touch and pain stimuli. The sensitivity of skin depends on the a. thickness of the epidermis. -The thinner the epidermis, the more sensitive the skin. b.number of receptor present. -More receptors more sensitive. Skin is the sensory organ of touch Respond to heat, cold, pressure, touch and pain stimuli. The sensitivity of skin depends on the a. thickness of the epidermis. -The thinner the epidermis, the more sensitive the skin. b.number of receptor present. -More receptors more sensitive.

10. Sensitive to touchNot sensitive to touch The parts of the body that have thin epidermis and many receptors sensitive to touch are,  Lips  Fingertips  Area behind the ears  Armpit  The back of the neck The part of the body, Elbow Knee Palm of the hand and sole of the foot Buttocks Like being inject? Upper arm/buttock

11. Explained the situation given by showing the pathway from stimulus, receptor involve and the response 1.Touch hot kettle. 2.Accidentally cut your hand. 3.Walk with barefoot on rough floor.

12. 1.3 Sense of smell