Sensory adaptations

Question 1

what are some sensory adaptations

Answer 1

-auditory (hearing)
-vision (sight)
-gustation (taste)
-traction (touch)

Question 2

how does the neuron transmit info

Answer 2

-receives stimulus and gets amplified
-moves down the dendrite
-makes electrical signal
-travels up the axon to the next neuron

Question 3

what is the auditory ability of dogs

Answer 3

-dogs can hear at higher frequencies than humans
-40,000 cycles/seconds in dogs (20,000 in humans)
-structure of a dogs ears enable sounds to be heard 4x further than human

Question 4

auditory pathway of dogs ears

Answer 4

external auditory meatus–> tympanic membrane–> malleus incus staples–> oval window membrane–> vestibular canal–> cochlea–> auditory nerve–> brain

Question 5

auditory testing in dogs

Answer 5

-brainstem auditory evoked response (BAER) testing detects unilateral or bilateral deafness
-congenital deafness and adult-onset deafness

Question 6

hearing range in cats

Answer 6

-hearing in an important sense for locating prey and their young when they go astray
-cats can detect sounds up to 80,000hz and as low as 20khz (wider range than dogs)

Question 7

hearing adaptations in the cat ear

Answer 7

-the pinna aids in the detection of sound
-it can rotate up to 180 and they can also move independently
-at a distance of 1 meter a cat can distinguish between two sounds 3 cm apart

Question 8

vision of dogs

Answer 8

-more rods than humans
-3x more sensitive to low light
-movement and shape

Question 9

different photoreceptors

Answer 9

-rods (low intensity, night vision)
-cones (bright light, high intensity light, colour resolution)

Question 10

how is vision processed

Answer 10

-light stimulus
-bounces in back of the eye
-goes to visual cortex of brain

Question 11

tapetum lucidum

Answer 11

-layer of reflective cells behind the retina in cats, dogs, and other animals
-helps capture additional light for night vision
-disadvantage: scatters of light makes it more difficult to resolve details of images

Question 12

cones in humans vs dogs vs cats

Answer 12

-humans have 3 kinds
-dogs have 2 types of cones they dont see red and orange spectrum
-cats have 3 cones but the red + orange in weak

Question 13

canine field of vision

Answer 13

-head shape affects field of vision
-brachycephalic breed- 200
-dolichocephalic breed- 270

Question 14

depth perception

Answer 14

-affected by degree of binocular overlap which is greater in flat-faced dogs
-average binocular vision is dogs is 30-60 degrees
-humans 140 degrees
-wider=less depth perception

Question 15

vision in cats

Answer 15

-cats eyes are large for their size
-set forward to provide a wide field of binocular vision (120)

Question 16

nictitating membrane

Answer 16

-third eyelid
-sits in the corner of their eyes and clears out dust

Question 17

olfactory neurons

Answer 17

-olfactory epithelium (olfactory receptor-first order neurons)
-olfactory bulb (mitral cell- second-order neurons)

Question 18

what olfactory organ is an extension of the brain

Answer 18

olfactory bulb (mitral cells)

Question 19

olfaction neuron quantity of dogs vs cats vs humans

Answer 19

220 M-2billion, 200M, 12-40M

Question 20

length of olfactory epithelium lining nasal passage way of dogs vs cats vs humans

Answer 20

150cm2, 20cm2, 3-4cm2

Question 21

sniffing

Answer 21

-disrupts normal breathing pattern to allow inhaled molecs to remain in the nasal passage longer
-series of rapid and short inhalations and exhalations

Question 22

olfactory adaptations that dogs have

Answer 22

-moist nose
-more independently moving nose (stereoscope)
-slits in the nose to not disrupt air going in when breathing out, new air isn’t diluted
-they know which side nostril the scent is coming from
-shelf of epithelium in nasal cavity

Question 23

vomeronasal organ

Answer 23

-composed of a pair of fluid-filled sacs with receptor cells
-present in both dogs and cats
-detects pheromones
-chemoreceptor organ
-first processing stage of the olfactory system
-neural receptors are different than in the main olfactory system
-impulse sent to the brain

Question 24

cat olfactory

Answer 24

-olfactory receptors in the olfactory epithelium are up to 5x more than humans
-have vomeronasal organ
-can have flehmen response
-30-50% exhibit plant-induced olfactory behaviour (cat nip)

Question 25

what does catnip contain

Answer 25

nepetalactone which causes agitation, head shaking, salivation

Question 26

what are the 5 things possible to taste

Answer 26

-sweet
-sour
-salty
-bitter
-umami

Question 27

taste in dogs

Answer 27

-dogs have ~1700 taste buds on the tongue; ~9000 in humans
-most abundant taste buds are sugar sensitive
-second most in acid

Question 28

taste bud mutations in dogs

Answer 28

-NSDTR have disrupted genes for bitter
-pug have disrupted genes for sweet

Question 29

taste in cats

Answer 29

-fewer tastebuds ~470
-they use smell and taste in selecting food
-can detect salty, bitter, and acidic flavours
-limited ability to taste sweet

Question 30

what does the cats filiform papillae help with

Answer 30

rasping the meat from the bone

Question 31

how do dogs drink

Answer 31

-curl their tongue and scoop water into their mouth
-throwing water into their mouth and catching it

Question 32

how do cats drink

Answer 32

-curl tongue
-tongue doesn’t dip below the surface
-the tongue touches the surface and creates a column of liquid

Question 33

cat drinking “lapping” cycle

Answer 33

-tongue is lifted drawing liquid up
-liquid is trapped in the ruggae (ridges) of the palate
-tongue helps trap the liquid
-swallowing occurs every 3 to 17 cycles

Question 34

touching in cats

Answer 34

vibrissae (whiskers) are important sensory organ

Question 35

vibrissae in cats

Answer 35

-found on muzzle, above eyes and on the back of the front wrist
-movable
-provide sensory information about position of prey in dim light
-upper and lower rows
-3x deeper
-used for air movements aswell

Question 36

cats and balance

Answer 36

-vestibular apparatus (ie. semicircular canals) in the inner ear more developed in cats
-can walk across fence rails, etc

Question 37

cats falling

Answer 37

-due to great balance
-they land feet down almost always
-start gaining the skill around 6-7 weeks old