7.2 The Mechanical Senses Flashcards
The ____ ____ respond to pressure, bending, or other distortions of the receptor. They include touch, pain, and other body sensations, as well as vestibular sensation, which detects the position and movement of the head.
mechanical senses
Vestibular sensation. When you move your head, the ____ ____ adjacent to the cochlea monitors movement and directs compensatory movements of your eyes.
vestibula organ
Sensations from the vestibular organ detect the direction of tilt and the amount of acceleration of the head. Vestibular sensations are critical for guiding eye-movement and ____ ____.
maintaining balance
The vestibular organ, consists of the ____, ____, and three semicircular canals.
saccule : utricle
The vestibular receptors are modified ____ receptors.
touch
Calcium carbonate particles called ____ lie next to hair cells, when the head tilts in different directions, the otoliths push against different sets of hair cells and excite them.
otoliths
The three ____ ____, oriented in perpendicular planes, are filled with a jellylike substance and lined with hair cells.
semicircular canals
Acceleration of the head at any angle causes the ____ ____ in one of these canals to push against the hair cells.
jellylike substance
Action potentials initiated by cells of the vestibular system travel through part of the ____ ____ ____ to the brainstem and cerebellum. (The eighth cranial nerve contains both an auditory component and a vestibular component.)
eighth cranial nerve
The ____ system, the sensation of the body and its movements, is not one sense but many, including discriminative touch (which identifies the shape of an object), deep pressure, cold, warmth, pain, itch, tickle, and the position and movement of the joints.
somatosensory
Receptor: ____ ____ ____. Location: near base of hairs and elsewhere in skin. Responds to: pain, warmth, cold.
Free nerve ending
Receptor: ____ ____. Location: hair-covered skin. Responds to: movement of hairs.
Hair-follicle receptors
Receptor: ____ ____. Location: hairless areas. Responds to: sudden displacement of skin; low-frequency vibration (butter).
Meissners corpuscles
Receptor: ____ ____. Location: both hairy and hairless skin. Responds to: sudden displacement of skin; high-frequency vibration.
Pacinian corpuscles
Receptor: ____ ____. Location: both hairy and hairless skin. Responds to: light touch.
Merkel’s disks