15.3

Question 1

what are chemoreceptors

Answer 1

receptors for smell and taste that respond to chemicals in a solution

Question 2

what is ansomia

Answer 2

temporary or permanent loss of the sense of smell

Question 3

what are olfactory sensory neurons

Answer 3

bipolar neurons with a thin apical dendrite that terminates in a knob with several olfactory cilia

Question 4

what happens after prolonged stimulation of olfactory receptors?

Answer 4

olfactory adaption

Question 5

what happens during olfactory transduction

Answer 5

an odorant binds to the olfactory receptor
a g protein turns up the signals already occurring which then sends a signal to cyclic AMP that will spread the msg even more by opening ion channels and cause impulse transmission

Question 6

what happens in the second half of olfactory transduction after the cAMP sends the secondary messenger

Answer 6

• axons of the olfactory sensory neurons synapse in the olfactory bulbs to the mitral cells that further amplify, refine, and relay signals
• mitral cells send the impulses down the olfactory tracts to the frontal lobe and to the thalamus, hypothalamus, amygdaloid, and other membranes of the limbic system

Question 7

what are taste buds and where are they located

Answer 7

the sensory receptor organs for taste which are located in the oral cavity with the majority of them located within the papillae of the tongue

Question 8

what are gustatory epithelial cells

Answer 8

• receptor cells that have microvilli called gustatory hairs that project into taste pores, bathed in saliva
• sensory dendrites coil around gustatory epithelial cells to send taste signals to the brain

Question 9

what is needed for chemicals to be tasted

Answer 9

chemical must be dissolved in the saliva, move into the taste pore and contact gustatory hairs producing graded potentials that release neurotransmitters to sensory dendrites

Question 10

what are the 5 tastes and what do they indicate

Answer 10

sweet - sugars
sour - hydrogen ions
salty - metal ions
bitter - alkaloids
unami - amino acids, glutamate, aspartate

Question 11

what happens when food chemicals to receptors?

Answer 11

depolarizes the gustatory epithelial cell membrane causing the release of a neurotransmitter that binds the dendrites of a sensory neuron