HMB200H1 Chapter Notes - Chapter 4.4: Motor Neuron, Myocyte, Olfactory Receptor
Document Summary
All different sensations have different sensory receptors: however, all have ion channel on their cell membranes. Ex/ touch: every hair on the body- able to detect vey slight displacements, dendrite of touch neuron- wrapped around the base of each hair, movmenet of the hair = stretching the dendrite. Opens stretch-sensitive channels in the dendrite"s membrane. Influx of na+ ions, triggering an action potential transduction: transforming sensory stimulus into nervous-system activity (electrical impulses) Ex/ vision: light particles hit chemical receptor in the eye chemical change in the eye, activates ion channel in the relay neurons. Ex/ odour: odourous molecule in the air lands on olfactory receptor (fits itself into a specially shaped compartment, opens chemical-sensitive ion channel. When tissue is damaged, injured cells release chemicals that activate pain nerves. All sensory systems employ ion channels for information conduction. Motor neurons in the spinal cord- responsible for activating muscles: motor neurons send impulses to synapses of muscles cells.
