Sensory Systems

Question 1

Perception of external stimuli is called…

Answer 1

…exteroception

Question 2

Perception of internal stimuli is called…

Answer 2

…interoception

Question 3

Classification of senses by the physical nature of their sensitivities:

Answer 3

• photoreception
• mechanoreception
• chemoreception
• thermoreception
• nocireception
• equilibrioception

Question 4

Approximate number of rods and cones in the eye?

Answer 4

Ca. 100 million rods, and ca. 5 million cones

Question 5

The optic nerve is formed from the axons of these cells:

Answer 5

retinal ganglion cells

Question 6

The 5 stages withing the visual pathway:

Answer 6

1. Photoreceptors (rods & cones)
2. Retinal bipolar interneurones
3. Retinal ganglion cells
4. Lateral geniculate nucleus of the thalamus
5. Primary visual area of the neocortex

Question 7

The cochlea belongs to which sensory system?

Answer 7

The auditory system

Question 8

Compartments of the ‘cochlear?’ tube:

Answer 8

• scala vestibuli
• cochlear duct
• scala tympani

Question 9

The cochlear duct is filled with…

Answer 9

….endolymph

Question 10

The scala vestibuli and the scala tympani are filled with…

Answer 10

…perilymph

Question 11

Sensory cells are found on the basilar membrane, which is in…

Answer 11

…the organ of Corti

Question 12

Approximately how many hair cells do we have?

Answer 12

Ca. 20 thousand

Question 13

The axons of these nerves form the auditory (vestibulocochlear) nerve proper

Answer 13

Spiral ganglia - clusters of bipolar cells connected to the hair cells

Question 14

The 5 stages of the auditory pathway:

Answer 14

1. Hair cells
2. Spiral ganglion cells
3. Several nuclei in the lower brainstem
4. Medial geniculate nucleus of the thalamus
5. Primary auditory area of the neocortex

Question 15

The two kinds of head movement sensed by the vestibular system:

Answer 15

• rotational

- linear

Question 16

3-D detection of movement is possible thanks to the:

Answer 16

semicircular system - a system of three semicircular canals perpendicular to one another

Question 17

Movement of the hair cells in the vestibular system stimulates these cells:

Answer 17

• vestibular ganglia

Question 18

Some projections of the vestibular system reach the neocortex via…

Answer 18

…the thalamus

Question 19

The olfactory system is directly connected to…

Answer 19

…the olfactory bulbs

Question 20

Approximately how many olfactory cells do we have?

Answer 20

Ca. 40 million

Question 21

The five basic chemoreceptor types in the gustatory system are sensitive to:

Answer 21

sweet, salty, sour, bitter, umami

Question 22

Stages in the gustatory pathway:

Answer 22

1. taste cells in taste buds
2. cranial nerve ganglia
3. brainstem gustatory nuclei
4. thalamus (ventral posterior nucleus)
5. insular cortex

Question 23

The ‘map’ of our body made up of cortical images in the neocortex is called…

Answer 23

…homunculus

Question 24

The somatosensory system collects signals from our body about…

Answer 24

touch, pressure, temperature, movement, and pain