1. EQ: How does an individual smell odors and hear things?
The Senses Part 2
EQ: How does an individual smell odors and hear things?

2. Sense of Smell

3. Olfactory Receptor cells
Bipolar neurons surrounded by columnar epithelial cells
Hair like cilia cover distal ends of neuron’s dendrites

4. Olfactory Bulb
Structure above nasal cavity that analyze impulses from receptor cells.

5. Humans use about 12 million olfactory receptors
Bloodhounds have about 4 billion

6. Sense of Hearing

7. Organs for hearing
Outer Ear
Middle Ear
Inner Ear

8. Outer Ear

9. Pinna
Outer flap used for catching sound waves

10. External Acoustic Meatus
AKA Ear Canal
Adult runs about 2.5 cm

11. Tympanic Membrane AKA Eardrum
Sound waves change the pressure of eardrum, thus producing vibrations

12. Middle Ear

13. 3 Main structures
Eardrum
Tympanic Cavity
Ossicles (3 bones

14. 3 Bones of Middle Ear
Malleus: Long handle attached to eardrum

15. 3 Bones of Middle Ear
Incus: The bridge bone between malleus and Stapes

16. 3 Bones of Middle Ear
Stapes: smallest bone that attaches to Cochlea

17. Sound travels through middle ear causing eardrum and ossicles to vibrate.

18. Inner Ear
Includes:
Semicircular Ducts
Cochlea
Eustachian Tube

19. Semicircular Ducts Filled with fluid Attached to Cochlea
Sends information about balance

20. Cochlea Spiral shaped organ filled with fluid.
Transforms sound into signal using pressure
Signal sent through the Vestibular Nerve and Cochlear Nerve

21. Eustachian Tube
Canal that drains fluid from middle ear into throat behind the nose

22. LEFT SIDE ACTIVITY Draw a diagram of an ear and a nose.
Label all of the parts and a description of their functions