The chemical sense of taste is also known as gustation.
Missing Word
gustation
Gustation is the special sense of taste, detected by receptor cells in taste buds. It relies on chemoreceptors that respond to dissolved molecules in saliva.
Category: Taste and Smell
Question 2
The loss of the sense of smell, which can follow head trauma, is called anosmia.
Missing Word
anosmia
Anosmia is the loss of olfaction. It can result from head injury that tears olfactory axons, from inflammation, or from some medications.
Category: Taste and Smell
Question 3
The swollen base of each semicircular canal, which holds hair cells whose stereocilia project into the cupula, is called the ampulla.
Missing Word
ampulla
The ampulla is the enlarged region at one end of each semicircular canal. When the head rotates, fluid in the canal pushes on the cupula and bends the hair cells inside the ampulla, signaling rotational movement.
Category: Hearing and Balance
Question 4
The coiled, snail-shaped chamber of the inner ear that holds the organ of Corti is the cochlea.
Missing Word
cochlea
The cochlea is the spiral portion of the inner ear that contains the receptors for hearing. Fluid waves inside it move the basilar membrane and bend hair cell stereocilia.
Category: Hearing and Balance
Question 5
Hearing and balance signals travel together to the brain stem in the vestibulocochlear nerve, cranial nerve VIII.
Missing Word
vestibulocochlear
The vestibulocochlear nerve has a cochlear branch for hearing and a vestibular branch for equilibrium. Both branches carry signals from inner ear hair cells to brain stem nuclei.
Category: Hearing and Balance
Question 6
Sensory receptors that respond to tissue damage and produce the sensation of pain are called nociceptors.
Missing Word
nociceptors
Nociceptors are usually free nerve endings that respond to strong mechanical, thermal or chemical stimuli that threaten tissue. Their signals are perceived as pain.
Category: Receptor Types
Question 7
Receptors such as muscle spindles and Golgi tendon organs that sense the position and movement of body parts are called proprioceptors.
Missing Word
proprioceptors
Proprioceptors are found in muscles, tendons and joints. They tell the CNS where body parts are and how they are moving, even with the eyes closed.
Category: Receptor Types
Question 8
The pigmented, muscular ring of the vascular tunic that controls the diameter of the pupil is the iris.
Missing Word
iris
The iris is the colored part of the eye. Its smooth muscle constricts or dilates the pupil to control how much light reaches the retina.
Category: Vision
Question 9
The tough white layer of the fibrous tunic that covers most of the surface of the eyeball is the sclera.
Missing Word
sclera
The sclera is the white of the eye, a dense connective tissue layer that protects the eye and anchors the extraocular muscles. The transparent cornea forms the rest of the fibrous tunic at the front of the eye.
Category: Vision
Question 10
Axons of the retinal ganglion cells bundle together and leave the eye as the optic nerve, cranial nerve II.
Missing Word
optic
The optic nerve is formed by ganglion cell axons exiting at the optic disc. It carries visual signals toward the optic chiasm and the brain.
Category: Vision
Question 11
The crossing of nerve fibers from one side of the central nervous system to the other is called decussation.
Missing Word
decussation
Decussation is the crossing over of a tract to the opposite side. It explains why each side of the brain receives sensation from and controls movement of the opposite side of the body.
Category: Sensory Pathways
Question 12
The lateral geniculate nucleus, which relays visual signals to the occipital lobe, is a nucleus of the thalamus.
Missing Word
thalamus
The thalamus is the main sensory relay of the diencephalon. Its lateral geniculate nucleus passes visual input from the optic tract to the primary visual cortex.
Category: Sensory Pathways
Question 13
Touch, pain and temperature from the face are carried into the brain stem at the pons by the trigeminal nerve, cranial nerve V.
Missing Word
trigeminal
The trigeminal nerve is the main sensory nerve of the face, scalp, mouth and nasal cavity. Its axons enter the pons and synapse in trigeminal nuclei of the brain stem.
Category: Sensory Pathways
Question 14
At the neuromuscular junction, somatic motor neurons release acetylcholine, which opens ligand-gated channels in the sarcolemma.
Missing Word
acetylcholine
Acetylcholine is the neurotransmitter of somatic motor neurons. Its binding opens ligand-gated cation channels that depolarize the muscle fiber and trigger contraction.
Category: Motor Responses
Question 15
Stroking the sole of the foot makes the big toe extend upward in the Babinski reflex, a response that is normal in infants but signals corticospinal tract damage in adults.
Missing Word
Babinski
The Babinski reflex is an upward extension of the big toe, often with fanning of the other toes. It is normal while infant motor pathways are still myelinating, but in an adult it points to damage of the corticospinal tract.
Category: Motor Responses