What Happens When I Get Burned

¶ … Burned

There are specialized cells called receptors that receive information about the environment and changes in that environment. Each kind of receptor reacts to a different kind of stimulus. For example, the receptors on the retina in the eye detect light. Receptors are all connected to nerve cells, and the nerve cells carry information from the receptor to the brain, where the signal is processed. The brain makes the decision about what to do with the information, such as move a part of the body to cause a reaction based on the information the receptors sent. However, in the case of an emergency situation, this normal interpretation process takes too long even though it is extremely fast, and instead another emergency plan is followed by the nervous system. When burned the body will experience a reflex reaction.

The skin has receptors that detect both pressure and temperature. In the case of an emergency situation such as burning one's hand on the stove, it is necessary to get the hand away from the heat source immediately so that the least amount of damage can be done to the tissue. The receptors in the skin that detect heat are called thermoreceptors. When burned, the thermoreceptors send a lot of impulses in rapid fire along the nerves to the spinal cord, a kind of S.O.S signal for help. Because it would take too long for the signal to reach the brain, the impulses travel along the relay neuron which is in the spinal cord. The impulse then exits into the motor neuron to the arm muscles. Immediately, the muscles receive the instructions to contract, thereby pulling the hand away from the heat source and rescuing it from further damage. This reaction which occurs without sending the impulse all the way to the brain is called a reflex; the path the impulse takes from the receptors through the nerves to the spinal cord and back to the muscles near the receptors is a reflex arc. Reflexes are always very fast and done for survival reasons.

This emergency survival action affects many bodily systems. The nervous system is obviously affected, as the root of the process takes place within that system, from the thermoreceptors, to the nerves, to the relay neuron. The reflex arc takes place through the nervous system. Of course, almost immediately the nerves also carry a signal to the brain with information about what has happened. People who touch a hot surface and reflexively pull away from it will notice that happen before they even realize they have burned themselves. That is because the reflex arc does not involve traveling all the way to the brain, because when the body is in harm's way, every minuscule moment of delay means further injury. The brain receives the signal after the reflexive action, and can interpret the events to decide what the next step should be. Perhaps the brain will send a signal to go rinse the hand under cold water, or to get the first aid kit out of the cabinet, or even to call a doctor for advice. Maybe first the brain will send a signal to the vocal cords to yell out in pain. The way that the muscular system is affected is by receiving the signal to contract in order to actually move the hand away from the hot surface, and following this signal to do so. The skeletal system is involved because when the muscles contract, they pull on the bones in the arm and hand, which is what pulls the entire limb away from the stove. Any other instructions that the brain sends to the body will also affect these systems. The nervous system will carry the message, the muscles will contract and relax, which will move the skeletal system by pulling bones in various directions. Every system is interconnected and involved in bodily actions.