Escape reflex: Difference between revisions
m Robot-assisted disambiguation: Painful |
removed "particularly common in animals" as it is tautological. non-animals don't have nervous systems. one could just as well claim that mammary glands are particularly common in mammals. |
||
Line 5: | Line 5: | ||
In higher animals examples of escape reflex include the [[withdrawal reflex]], e.g., the withdrawal of a hand in response to a [[Pain and nociception|pain]] stimulus. [[Sensory receptor]]s in the stimulated body part send signals to the [[spinal cord]] along a [[sensory neuron]]. Within the spine a [[reflex arc]] switches the signals straight back to the muscles of the arm ([[effector]]s) via an intermediate neuron ([[interneuron]]) and then a [[motor neuron]]; the muscle contracts and the arm jerks. Only three nerve cells are involved, and the [[brain]] is only aware of the response after it has taken place. |
In higher animals examples of escape reflex include the [[withdrawal reflex]], e.g., the withdrawal of a hand in response to a [[Pain and nociception|pain]] stimulus. [[Sensory receptor]]s in the stimulated body part send signals to the [[spinal cord]] along a [[sensory neuron]]. Within the spine a [[reflex arc]] switches the signals straight back to the muscles of the arm ([[effector]]s) via an intermediate neuron ([[interneuron]]) and then a [[motor neuron]]; the muscle contracts and the arm jerks. Only three nerve cells are involved, and the [[brain]] is only aware of the response after it has taken place. |
||
Escape reflex arcs |
Escape reflex arcs have a high survival value, enabling organisms to take rapid action to avoid potential danger. |
||
Various animals may have specialized escape reflex circuits. |
Various animals may have specialized escape reflex circuits. |
Revision as of 20:52, 25 January 2007
Escape reflex, a kind of a escape response, is a simple reflectory reaction in response to stimuli indicative of danger, that initiates an escape motion of an animal.
Escape reflexes control, e.g., the seemingly chaotic motion of a cockroach running from under the foot when one tries to squash it.
In higher animals examples of escape reflex include the withdrawal reflex, e.g., the withdrawal of a hand in response to a pain stimulus. Sensory receptors in the stimulated body part send signals to the spinal cord along a sensory neuron. Within the spine a reflex arc switches the signals straight back to the muscles of the arm (effectors) via an intermediate neuron (interneuron) and then a motor neuron; the muscle contracts and the arm jerks. Only three nerve cells are involved, and the brain is only aware of the response after it has taken place.
Escape reflex arcs have a high survival value, enabling organisms to take rapid action to avoid potential danger.
Various animals may have specialized escape reflex circuits.
Examples of escape reflexes
- Withdrawal reflexes
- Ducking (flexing the neck to protect the head)
- Jumping to loud sounds
- Other
- Lateral giant escape in crayfish
- Escape reflex in squid
- Dorsal ramp interneuron (DRI) action in Tritonia molluscs.