Chapter 46 Animal Sensory Systems and Movement

signal b/w individuals that causes a change in behavior or physiology

• 1. transduction - conversion of external stimulus to an internal signal through action potential
• 2. amplification of signal
• 3. transmit to central nervous system
• 4. integration - processing with other signals

sense danger/harmful stimuli

sense changes in temp

sense distortion caused by touch or pressure

perceive different types of molecules

sense wavelengths of light

sense electric field (only sometimes present)

• "voltage"
• created when plasma membrane separates charges

• inside of cell has become more positive
• in hair cells, causes an inflow of calcium ions, triggering an increase in amount of neurotransmitter released at synapse

cause inside cell to become more negative

They depolarize according to the loudness of the sound (louder the sound, the higher the firing rate of action potentials)

• cells highly specific to a certain type of information
• sensory neurons send their signals to certain parts of the brain only

• ability to sense wavelength changes in air pressure
• depends on # of waves (frequency)
• different frequencies = pitches

• found in crabs
• fluid-filled organ with calcium-rich structure that senses pressure due to gravity

• direct phys pressure conforms the ion channel (either making it hyperpolarize or depolarize)
• leads to new action potential from sensory neuron

• stiff outgrowths that comprise hair cells
• when pressure is applied, the stereocilia lean and opens up a pathway for the ions to enter

• 9+2 arrangement of microtubules
• part of hair cells

• outer ear
• middle ear
• inner ear
• all separated by a membrane

funnels sound into ear canal