Key terms
50 terms- Sensory transduction§43.1
- Converting stimulus energy into a change in membrane potential
- Receptor potential§43.1
- Graded potential in a receptor; its size scales with stimulus strength
- Labeled line principle§43.1
- The brain identifies a sensation by which neuron carried it, not by the stimulus itself
- Tonic receptor§43.1
- Slow-adapting; keeps firing during a sustained stimulus (pain, proprioception)
- Phasic receptor§43.1
- Fast-adapting; fires at the change then goes quiet (smell, light touch)
- Exteroceptor§43.1
- Receptor that monitors the external environment
- Interoceptor§43.1
- Receptor that monitors internal body conditions
- Proprioceptor§43.1
- Interoceptor reporting body/limb position — muscle spindles, Golgi tendon organs
- Nociceptor§43.1
- Free nerve ending that signals tissue damage — pain
- Pacinian corpuscle§43.2
- Deep, layered, fast-adapting receptor for pressure and vibration
- Meissner corpuscle§43.2
- Shallow fast-adapting receptor for light touch and fine texture
- Merkel cell§43.2
- Shallow slow-adapting receptor for sustained touch, edges and shape
- Muscle spindle§43.2
- Stretch receptor inside muscle; drives the knee-jerk reflex
- Golgi tendon organ§43.2
- Tension receptor in tendons; protects against overload
- Hair cell§43.3
- Mechanoreceptor with stereocilia used in hearing, balance, and the lateral line
- Stereocilia§43.3
- Hair-cell projections; bending toward the tallest depolarizes the cell
- Lateral line system§43.3
- Fish system of neuromasts detecting water movement — "distant touch"
- Neuromast§43.3
- Cluster of hair cells under a gelatinous cupula in the lateral line
- Tympanic membrane§43.3
- The eardrum; vibrates and drives the ossicles
- Ossicles§43.3
- Malleus, incus, stapes — the three middle-ear amplifying bones
- Oval window§43.3
- Membrane the stapes strikes, sending pressure waves into the cochlea
- Round window§43.3
- Membrane that bulges to release cochlear pressure waves
- Cochlea§43.3
- Coiled inner-ear organ of hearing with three fluid-filled chambers
- Organ of Corti§43.3
- Hair-cell structure on the basilar membrane; the actual hearing receptor
- Basilar membrane§43.3
- Membrane whose stiffness gradient sorts pitch by place — base = high, apex = low
- Tectorial membrane§43.3
- Overlying flap that shears against stereocilia to bend them
- Eustachian tube§43.3
- Connects middle ear to throat; equalizes pressure
- Utricle and saccule§43.3
- Otolith organs sensing gravity and linear acceleration
- Otolith§43.3
- Calcium carbonate crystal whose weight shifts and bends hair cells
- Semicircular canals§43.3
- Three perpendicular canals detecting rotational acceleration
- Cupula§43.3
- Gelatinous cap in the ampulla that deflects with fluid motion
- Taste bud§43.4
- Cluster of taste receptor cells within a papilla
- Umami§43.4
- The savory/glutamate taste — the fifth basic taste
- Gustducin§43.4
- G protein used by sweet, bitter, and umami receptors
- Olfactory epithelium§43.4
- Sheet of bipolar olfactory neurons in the roof of the nasal cavity
- Glomerulus (olfactory)§43.4
- Bulb structure where all neurons with the same receptor converge
- Vomeronasal organ§43.4
- Jacobson's organ; detects pheromones
- Ommatidium§43.5
- One optical unit of an arthropod compound eye
- Accommodation§43.5
- Focusing by changing lens shape via the ciliary muscles
- Fovea§43.5
- Cone-packed retinal pit giving the sharpest vision
- Optic disc§43.5
- Where the optic nerve exits; no photoreceptors — the blind spot
- Rod§43.5
- Photoreceptor for dim light and peripheral vision; no color; uses rhodopsin
- Cone§43.5
- Photoreceptor for bright light, color, and sharp detail; three spectral types
- Rhodopsin§43.5
- Visual pigment: retinal bound to opsin
- Retinal§43.5
- Vitamin-A-derived molecule that isomerizes from 11-cis to all-trans in light
- Transducin§43.5
- G protein activated by light-struck rhodopsin
- Optic chiasm§43.5
- Crossing point where nasal retinal fibers switch sides
- Lateral geniculate nucleus§43.5
- Thalamic relay between retina and visual cortex
- Pit organ§43.6
- Infrared-sensing organ of pit vipers and some snakes
- Ampullae of Lorenzini§43.6
- Electroreceptors of sharks and rays