Homeostasis is the body’s ability to maintain a constant balance between the internal environment and external environment at a constant rate, despite changes which may affect our external environment such as body temperature and the amount of water in our bodies. By keeping this internal balance it allows our bodies to function efficiently. The negative feedback loop is produced when changes to our internal environment changes from its normal range. In this instance the brain and the nervous system help to get our internal environments back to its normal state. An example of this is when an individuals body is too hot and our body begins to sweat in order for us to cool down. Our internal receptors react to make sure that we can return to out normal level. These receptors are needed in the negative feedback loop to help send a message about environmental stimuli to our central nervous system, after this our bodies then send signals to an effector, to respond to the stimuli. By doing all of this our bodies can bring our internal environment back to its normal self. Heart Rate:
The Sino atrial node, which is otherwise known as the heart’s pacemaker is located at the top of the right atrium in the heart. This is what helps to decide what speed our hearts should be beating depending on the situation we are in. When we exercise our sympathetic nerves speed up the heart rate because we would be needing more oxygen in our lungs as we are working harder which means our hearts will then beat at a faster rate, but once we stop the physical activity which we are doing or parasympathetic nerves help to slow down the heart rate as we wouldn't be needing as much oxygen. Receptors are connected to a control centre, which is the brain. When our brains receive information about a change to our internal environment, it then sends out some signals along nerves that in turn will bring out internal environment back to its normal rate. As our heart rate is...
Please join StudyMode to read the full document