Chapter 10. Somatic and Special Senses. Sensory Receptors = detect environmental changes and trigger impulses that travel to central nervous system for interpretation 2 major categories of sensory receptors: 1. somatic senses = touch, pressure, temperature and pain
Somatic and Special Senses
1. Chemoreceptors = changes in chemical concentration
2. Pain Receptors = detect tissue damage
3. Thermoreceptors = temperature differences
4. Mechanoreceptors = pressure or movement differences
5. Photoreceptors = light energy
Did you know? Humans have about 12 million olfactory receptor cells. Bloodhounds have about 4 billion such cells!
Did you know? Cats have only about 473 taste buds and dogs have about 1,700…..that is why they are satisfied with a less varied diet than humans.
Auricle (pinna) = funnel structure that collects sound
External Acoustic Meatus (canal) = transports sound
Tympanic Cavity= air filled space of temporal bone
Auditory Ossicles = 3 small bones within the middle ear/tympanic cavity: malleus, incus, stapes
= Connects the middle ear to the throat
SOUND TRANSMISSION have about 1,700…..that is why they are satisfied with a less varied diet than humans.
Labyrinth= system of communicating chambers and tubes
2 parts to labyrinth:
Cochlea= houses organ of hearing (organ of Corti)
Organ of Corti: contains hair cells (receptors on the basilar membrane) that extend into the cochlear duct
Static Equilibrium=maintain head position when still
Dynamic Equilibrium = maintain balance when moving