USABO SEMI COMPLETE SET KEY
CONCEPTS AND REVISION NOTES
◉ Lateral inhibition in the retina
Answer: Horizontal cells inhibit neighboring pathways to sharpen
visual contrast and edge perception.
◉ Optic chiasm processing rule
Answer: Visual information crosses so each hemisphere processes
the opposite visual field.
◉ Taste receptor mechanisms by flavor
Answer: Sweet, umami, bitter use GPCRs; sour and salty use direct
ion channels.
◉ Taste cell specificity
Answer: Each taste cell expresses one receptor type; any tongue
region can detect any taste.
◉ Olfactory transduction mechanism
Answer: Odorant binds GPCR neuron → cAMP cascade opens
Na⁺/Ca²⁺ channels → cell depolarizes.
◉ Sarcomere behavior during contraction
CONCEPTS AND REVISION NOTES
◉ Lateral inhibition in the retina
Answer: Horizontal cells inhibit neighboring pathways to sharpen
visual contrast and edge perception.
◉ Optic chiasm processing rule
Answer: Visual information crosses so each hemisphere processes
the opposite visual field.
◉ Taste receptor mechanisms by flavor
Answer: Sweet, umami, bitter use GPCRs; sour and salty use direct
ion channels.
◉ Taste cell specificity
Answer: Each taste cell expresses one receptor type; any tongue
region can detect any taste.
◉ Olfactory transduction mechanism
Answer: Odorant binds GPCR neuron → cAMP cascade opens
Na⁺/Ca²⁺ channels → cell depolarizes.
◉ Sarcomere behavior during contraction
