AP Biology Nervous Systems Part 4
Stronger depolarizing stimulus LE 48-12 Stimuli Stimuli Stronger depolarizing stimulus +50 +50 +50 Action potential Membrane potential (mV) Membrane potential (mV) Membrane potential (mV) –50 Threshold –50 Threshold –50 Threshold Resting potential Resting potential Resting potential Hyperpolarizations Depolarizations –100 –100 –100 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 6 Time (msec) Time (msec) Time (msec) Graded potential hyperpolarizations Graded potential depolarizations Action potential
Action potential moving toward the CNS Schwann cell Depolarized region (node of Ranvier) Cell body Myelin sheath Axon
Dendrites of the neurons
Summation and the Threshold potential Stimuli Stimuli Stronger depolarizing stimulus +50 +50 +50 Action potential Membrane potential (mV) Membrane potential (mV) Membrane potential (mV) –50 Threshold –50 Threshold –50 Threshold Resting potential Resting potential Resting potential Hyperpolarizations Depolarizations –100 –100 –100 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 6 Time (msec) Time (msec) Time (msec) Graded potential hyperpolarizations Graded potential depolarizations Action potential
Heat Light touch Pain Cold Hair Epidermis Dermis Hypodermis Nerve Stimulus receptors Heat Light touch Pain Cold Hair Epidermis Dermis Hypodermis Nerve Connective tissue Hair movement Strong pressure
Middle and Inner Ear
Inside the Cochlea
Cochlear Duct
Balance and the Inner ear
Taste
Smell
. Lateral line Lateral line canal Scale Opening of lateral line canal Epidermis Neuromast Segmental muscles of body wall Lateral nerve Cupula Sensory hairs Supporting cell Hair cell Nerve fiber
Statosyst Ciliated receptor cells Cilia Statolith Sensory nerve fibers
Tympanum for hearing
. Tympanic membrane 1 mm