1. The Senses

2. Senses in Animals Survival
Used for survival to tell animals what is going on around them
Sense organs
Ears, nose, tongue, skin, eyes

3. Senses in Animals Planarian Lives in ponds, rivers, and lakes
2 sense organs
Knobs– used for detecting water currents
Eyespots– only able to tell light from dark

4. Detects sound from the front of the leg
Senses in Animals
Earthworms
-light detectors
-located just below the skin
- Cricket
Detects sound from the front of the leg
Antennas detect feeling
Uses a compound eye for seeing

5. Senses in Animals Snake Snakes eyes are similar to human eyes
Snakes use their tongue to smell
They shoot their tongue out and it catches air molecules
They bring the air back into its mouth , where the sense of smell organ is located

6. Human Sense Organs The Eye Path of light through the eye Sclera Iris
Pupil
Cornea
Lens
Retina
Vitreous humor

7. The eye Light passes and bends first through the cornea
Then light passes through the pupil and the lens
The light bends again in the lens towards each other
Light then passes through the vitreous humor
The vitreous humor is clear. The light finally reaches the retina

8. The retina is made up of rods and cones
Rods detect motion and light or dark
Cones detect color
Cones are nerve cells that detect color
There are three types of cones, each type detects only one color-----red, green, or blue
All the other colors are cones acting together

9. The optic nerve Carries the message from the eye to the vision
Center of the brain
2 things happen at the vision center
The brain interprets the message
The image is rotated right-side up

10. The Ear 3 parts Outer, Middle, Inner Outer Ear
The only part that is visible of the entire ear
The ear flap helps direct the sound waves into the ear
Sound waves travel through the ear canal and bump against the ear drum

11. Middle Ear
The vibration of the sound waves cause the anvil, hammer, and the stirrup to move
The stirrup is also connected to a membrane that vibrates with the motion of the ear bones

12. Inner ear
The cochlea contains nerve cells that are connected to the auditory nerve
The auditory nerve takes the message to the brain to be interpreted
Semicircular Cells
Nothing to do with hearing
Helps maintain balance

13. The Tongue The tongue contains taste buds that detect taste
They detect the chemical molecules in food
4 different types
Sour
Salty
Sweet
bitter

14. The Nose Detects gas molecules in the air
Neurons line the top of the nasal chamber
There are 7 different types of nerve cells in the nose that detect a different odor
The olfactory nerve takes messages to your brain and the cerebrum interprets the message

15. The Skin 2 different layers for the skin The epidermis –outside
The Dermis—inner part
5 nerve cell types
Pain
Pleasure
Touch
Heat
Cold

16. Most nerve cells are found in the dermis
But both the epidermis and the dermis share the pain cell
From the skin, the nerve cells travel to the cerebrum to be interpreted
They are perceived as cold, hot pain, pleasure, or touch