18/02/2014 § Leave a comment
Can you believe this is the last unit, ‘cause I sure can.
In E.1 we have a few words (okay, a lot of words) to remember but three important ones are stimulus, response, and reflex. The definition of stimulus is easy enough to remember if you remember your alphabet, specifically CDE. A stimulus is a Change in the internal/external environment that is Detected by a receptor and Elicits a response. EASY (I wish). A response is produced by a stimulus and produces a change in the organism. A reflex is a rapid, unconscious response to a stimulus. The elements of responses of animals to stimuli include not only receptors but all types of neurons (namely sensory neurons, relay neurons, and motor neurons), synapses, and effectors.
We also need to draw and label a diagram on the reflex arc for pain including the following elements (as well as most everything listed above):
- sensory pain signals enter dorsal root of spinal cord
- interneurons in spinal cord stimulate flexor motor neurons
- interneurons inhibit extensor motor neurons
- motor neurons exit spinal cord & stimulate flexor muscles
- extensor muscles relax
- withdrawal of leg
- neurotransmitter = acetylcholine
- bisynaptic reflex