Lecture #13: Special Senses: Hearing, Equilibrium, and Vision

These flashcards cover the key concepts from the lecture on special senses including hearing, equilibrium, smell, taste, and vision.

What are the main types of sensory cells involved in special senses according to the lecture?

Mechanical (Hearing), Chemical (Smell and Taste), and Electromagnetic (Vision) sensory cells.

What do hair cells in the cochlea do?

Hair cells are responsible for detecting sound waves; they do not regenerate.

Which parts of the inner ear are responsible for balance?

Utricle, Saccule, and Semicircular Canals.

What is the range of normal human hearing in hertz (Hz)?

20 to 20,000 hertz.

What structure transmits sound vibrations from the middle ear to the inner ear?

The oval window.

How is sound frequency detected in the organ of Corti?

Different frequencies cause vibrations at different locations along the basilar membrane (base for high frequencies, apex for low frequencies).

What is sensorineural deafness?

Hearing loss due to damage to neural structures from the cochlear hair cells to the auditory cortex.

What role do the macula receptors in the utricle and saccule play?

They house linear equilibrium receptor regions that respond to changes in head position and gravity.

What happens when hair cells bend toward the tallest stereocilia?

It opens mechanically gated ion channels, leading to depolarization and the release of glutamate.

What are the five basic taste sensations?

Salty, Sour, Sweet, Bitter, and Umami.

How does the olfactory system process smell?

Odorants bind to receptors, activate G proteins, and lead to depolarization of the sensory neuron.

What is the function of the retina in the eye?

The retina contains photoreceptors (rods and cones) that detect light and convert it into neural signals.

What adaptive process occurs when moving from dark to bright light?

Light Adaptation, which involves the constriction of pupils and the rapid adaptation of cone cells.

What is the significance of the spiral organ (organ of Corti)?

It contains hair cells that transduce sound vibrations into neural signals.

What type of pigments do photoreceptors in the retina contain?

Rhodopsin in rods and three types of photopsins in cones.

What adaptation occurs when moving from bright light to darkness?

Dark Adaptation, which enhances retinal sensitivity as rhodopsin accumulates in rods.