Ch. 50 - Sensory & Motor Mechanisms: Sensory Pathways & Hearing

Question 1

what are the four functions of sensory pathways?

Answer 1

1. reception & transduction of signals by PNS neurons
2. transmission by CNS neurons
3. perception
4. amplification of signals

Question 2

what is sensory adaptation?

Answer 2

the cessation of signal transduction due to constant stimulation: getting used to something

Question 3

what type of stimuli do mechanoreceptors receive?

Answer 3

pressure changes: touch, stretch, hearing, and balance

Question 4

what type of stimuli do chemoreceptors receive?

Answer 4

chemicals: taste in the mouth, smell in the nose

Question 5

what type of stimuli do photoreceptors receive?

Answer 5

light and / or colour, found in the eye

Question 6

what type of stimuli do thermoreceptors receive, and where are these receptors found?

Answer 6

change in temperature: found in the skin and hypothalamus of the brain

Question 7

what stimuli do pain receptors receive?

Answer 7

pain: extreme temperature, extreme pressure, or chemical pain. found everywhere outside & inside body

Question 8

what is the broad pathway for sound waves travelling in the ear?

Answer 8

1. auditory canal funnels sound to tympanic membrane
2. tymp. membrane amplifies sound through malleus, incus, and stapes bones
3. stapes transmits sound as vibrations to to the oval window and cochlea
4. hair cells in cochlea receive vibratory stimuli and transmit it to the brain

Question 9

what is the cochlea?

Answer 9

a long, snail shaped structure in the ear that transmits vibrations, divided in half by the organ of corti

Question 10

what is the organ of corti?

Answer 10

a long row of hair cells found in a basiliar membrane, with the hairs themselves suspended within a tectorial membrane

Question 11

what is the function of hair cells?

Answer 11

hair cells “bend” due to vibrations in the tectorial membrane, and the hair cells send a stimuli down the auditory nerve to tell the brain a sound just happened

Question 12

what three equilibrium structures are found within the inner ear?

Answer 12

the utricle, saccule, and semicircular canals

Question 13

what is the function of the utricle?

Answer 13

to sense horizontal position and movement

Question 14

what is the function of the saccule?

Answer 14

to sense vertical position and movement

Question 15

what is the function of the semicircular canals?

Answer 15

to sense rotational acceleration and keep your body balanced

Question 16

how do fish hear?

Answer 16

vibrations pass from the skull or swim bladder to hair cells in the inner ear

Question 17

what is the function of the lateral line in fish?

Answer 17

lateral line contains “gel”, which is moved by water, which moves hair cells, which allows them to detect movement & vibrations