BIOL 1013 Lecture Notes - Lecture 6: Parasympathetic Nervous System, Sympathetic Nervous System, Autonomic Nervous System
Document Summary
Outside world receptor potentials action potentials synaptic transmissions sensation . Blocking pain receptors- inhibit opening of ca at axon terminals of presynaptic neurons; inhibit closing of. K; block receptors on post synaptic neurons; inhibit na from entering synaptic neuron (block signals from reaching the post synaptic neuron) During emergencies and stressful situations- increase heart rate, dilate arteries to muscles, constrict arteries to gi (gastrointestinal tract) When resting- decrease heart rate, constrict arteries to muscles, and send more blood to gi. Parasympathetic nervous system: rest and digest, calm down. General senses- all over the body: touch, temperature, pain. Special sense- cephalization: hearing and equilibrium, vision, smell, taste. Adaptational advantages- doesn"t take long to reach the brain. Receptor potentials are graded potentials that occur in sensory receptor cells. Sensory adaptation- getting used to a constant stimulus over time. Sensory receptors generate fewer action potentials under continuous stimulation.
