BIOL 205 Lecture Notes - Lecture 11: Far-Sightedness, Presbyopia, Basilar Membrane

• School: University of Calgary
• Department: Biology
• Course: BIOL 205
• Professor: Peter Neuhaus

Document Summary

Animal sensations begin as stimuli detected by sensory receptor cells. Sound and balance are perceived as vibrations and are detected by mechanoreceptors. Chemoreceptors detect chemical signals as taste or smell. Sensory receptors transduce stimulus energy and transmit signals to cns (stimulus is transferred into energy so receptors can detect them) Sensation involves converting energy into a change in the membrane potential of sensory receptors. Whe(cid:374) a sti(cid:373)ulus i(cid:374)put to (cid:374)ervous syste(cid:373) is pro(cid:272)essed, a (cid:373)otor respo(cid:374)se (cid:373)ay (cid:271)e generated. This may involve a simple reflex or more elaborate processing. Cows, sharks, birds have electromagnetic sensors (migrating, find food) Mechanoreceptors- stretch receptors in skeletal muscles, hair cells may have specialized cilia on receptor cells. Sensory transduction- receptor cells convert one type of signal to an electrical signal. Stronger the stimulus, greater the receptor potential. Can trigger action potential in adjacent neurons, forms synapse with sensory neurons. Frequency of action potential= intensity of sense.