Sensory System- Chapter 44

Question 1

sense external stimuli

Answer 1

exteroceptors

Question 2

sense internal stimuli

Answer 2

interoceptors

Question 3

stimulated by mechanical forces such as pressure

Answer 3

mechanoreceptors

Question 4

detect chemicals or chemical changes

Answer 4

chemoreceptors

Question 5

react to electromagnetic and thermal energy

Answer 5

energy-detecting receptors

Question 6

four step process of sensory receptors

Answer 6

(1) stimulation
(2) transduction-receptor potential in sensory cell created
(3) transmission- action potential in sensory neuron
(4) interpretation- CNS processing

Question 7

sensory cells respond to stimuli via _____________ in their membranes, depolarize receptors referred to as _____________

Answer 7

stimulus-gated ion channels

receptor potential

Question 8

transmit impulses based on cell damage, perceived as pain, most are at free nerve endings

Answer 8

nociceptors

Question 9

naked dendritic endings of sensory neurons, sensitive to changes in temperature, cold receptors more numerous than warm receptors

Answer 9

thermoreceptors

Question 10

contain sensory cells with ion channels that open in response to membrane distortions

Answer 10

mechanreceptors

Question 11

monitor muscle length and tension, provide information about the relative position or movement about an animals body parts (include muscle spindles and golgi tendon organs)

Answer 11

proprioceptors

Question 12

monitor blood pressure, found in carotid sinus and aortic arch, detect tension or stretch in the walls of these blood vessels

Answer 12

baroreceptors

Question 13

specialized cells with cytoplasmic extensions called stereocilia, send APs when they bend, used for detection of water current, hearing, and balance

Answer 13

hair cells

Question 14

lateral line system in fish contains _________ in a gelatinous ________, stereocilia are bent and detect currents

Answer 14

hair cells

cupula

Question 15

perceived as sound, bending of stereocilia

Answer 15

hearing

Question 16

3 chambers filled with fluid in inner ear, wrapped in a coil

Answer 16

cochlea

Question 17

has a basilar membrane with hair cells, vibrations of the basilar membrane’s hair cells press the stereocilia against the tectorial membrane, nerve impulses to brain = sound

Answer 17

organ of corti

Question 18

a few mammals have the ability perceive presence and distance of objects by sound,

Answer 18

echolocation

Question 19

in vertebrates, the gravity receptors consist of two chambers in the membranous labyrinth

Answer 19

balance

Question 20

utricle and saccule are hair cells embedded in the otolith membrane, head movement causes the otolithic membrane to move and stereocilia to bend

Answer 20

balance

Question 21

detect angular acceleration in any direction, ampullae are the chambers, have hair cells in the cupula, acceleration moves the fluid in the canals

Answer 21

semicircular canals

Question 22

can bind to particular chemicals in extracellular fluid, membrane of sensory neuron becomes depolarized and produces action potentials, sense taste smell and blood composition

Answer 22

chemoreceptor

Question 23

broken down into five receptor types (sweet, sour, salty, bitter, and umami)

Answer 23

taste

Question 24

collections of chemosensitive cellsassociated with afferent neurons

Answer 24

taste buds

Question 25

flies have chemoreceptors located on their _______

Answer 25

feet

Question 26

involves neurons located in the upper portion of the nasal passages, transmit impulses directly to the brain via the olfactory nerve, humans have over 50 of receptors

Answer 26

olfaction

Question 27

found in the aortic and carotid bodies, sensitive primarily to the pH of plasma

Answer 27

peripheral chemoreceptors

Question 28

found in the medulla oblongata of the brain, sensitive to the pH of cerebrospinal fluid

Answer 28

central chemoreceptors

Question 29

begins with the capture of light energy by __________, many invertebrates have photoreceptors clustered in an _________

Answer 29

photoreceptors

eyespot

Question 30

What are the 4 phyla that evolved well-developed image forming eyes?

Answer 30

annelids, mollusks, arthropods, chordates

Question 31

What are the 2 parts of the retina?

Answer 31

rods- black and white vision when illumination is dim

cones- color vision and high visual acuity (sharpness), most are located in the central region of the retina

Question 32

rods have _________, broad ranging pigment that detects values

Answer 32

rhodopsin

Question 33

cones have ________, each with a different amino acid sequence, the more you have the more color you see

Answer 33

photopsins

Question 34

carnivores are __________, they have 2 types of cones

Answer 34

dichromats

Question 35

humans are _________, have 3 kinds of cones (colorblind humans are usually dichromats)

Answer 35

trichomats

Question 36

birds are _______, have 4 cones, can see what we see and UV light

Answer 36

tetrachromats

Question 37

a transparent structure that completes focusing of light onto the retina

Answer 37

lens

Question 38

external layer of cells of the retina (furthest away from the eye)

Answer 38

photoreceptors

Question 39

middle later of cells in the retina

Answer 39

bipolar cells

Question 40

layer of cells closest to the eye in the retina

Answer 40

ganglion cells

Question 41

How is the optic nerve stimulated?

Answer 41

hits photoreceptors, stimulate to front and transmit impulse to brain

Question 42

How is vision processed?

Answer 42

action potentials are relayed from retina to thalamus, then to occipital lobe of cerebral cortex, each hemisphere receives input

Question 43

when 2 fields of vision overlap, allows 3-D images to be perceived and depth, having eyes on the sides of the head reduces this

Answer 43

binocular vision

Question 44

the only vertebrates that can sense infrared radiation are _______, they have a pair of pit organs on either side of the head which locate heat source

Answer 44

snakes

Question 45

can sense electrical currents generated by the muscle contraction of their prey, seen in sharks rays and skates

Answer 45

ampullae of lorenzini

Question 46

allows eels, sharks and many birds to navigate along the magnetic fields of the Earth

Answer 46

magnetoception