Homeostasis is the process of maintaining a constantinternal environment in response to change in the external environment. Homeostasisinvolves the maintenance of many different controllable things within the humanbody. This includes; oxygen levels, bloodpressure, carbon dioxide levels, pH, water levels, hormones, body temperatureand glucose levels.
All of these things remain at a constant regulated rateeven if there is a change in the external environment to the body. Within thebody all of the body cells and tissues are used for homeostasis. The changeswhich occur outside the environment are detected by receptors and when certainchanges are detected the body initiates the appropriate response. A homeostaticresponse can either be a behavioural change or physiological changes.For instance; when our body temperature decreases we put onextra clothes in order for us to become warmer and increase our bodytemperature. This is an example of behavioural response to changes in theexternal environment. However, a physiological response to changes in theenvironment would be when our blood glucose levels decrease due to the releaseof insulin and glucagon being realised in order to maintain these levels.
Glucagon is a hormone formed in the pancreaswhich promotes the breakdown of glycogen to glucose in the liver. The releaseof glucagon in the body will result in the release of glucose in the body’scells.Homeostasis involves coordination between the nervous andthe endocrine system. The nervous system is divided into two parts; the Centralnervous system; made up of the brain and the spinal cord and the second part ofthe nervous system which branches off to the rest of the body. The responseswhich are given off by the nervous system are given off quicker but are shorterthan the responses given by the endocrine system.
The endocrine system is madeup of glands which play the important role in realising hormones into the bodywhen they are needed. The body then responds to changes in the external environmentin many different ways. Some examples of homeostasis response would be a changein the heart rate, blood pressure, body temperature, blood glucose levels and achange in the breathing rate.When exercising or taking part in a activity the muscles organsand tissues in the body require more oxygen in order to be able to functionproperly and to allow you to sustains this increased level of activity. Thereis a greater demand for oxygen in the body and the homeostatic response to thisneed is to increase the cardiac output in order to increase the oxygen levelsin the blood. This also means that the body cells are producing more carbon dioxidewhich needs to be removed as it is a waste product of the body. Therefore when your body detects a change in your level ofactivity it then causes the heart rate to increase.
This is so that your heartcan pump a larger volume of blood, containing oxygen, around the body at aquicker rate. It also means that the carbon dioxide can be removed via theblood as it is being produced to keep the cells clean, healthy and able tofunction.Breathing rate is another factor which changes duringexercise as a homeostatic response to changes in activity levels. Breathingrate also greatly affects the oxygen levels within the body. Oxygen control andbreathing rate is all controlled and regulated by a respiratory control systemwhich is located in the brain stem.
This control system constantly monitors thelevel of oxygen and carbon dioxide in the bloodstream. It then make a adjustmentsto your breathing rate in order to maintain a healthy, constant balance ofoxygen and carbon dioxide levels and creates a state of homeostasis within thebody. When exercising the body has an increased demand for oxygen in order toallow cells to function correctly. This means that the body makes changes tothe depth and rate of breathing in order to meet these demands.
There arereceptors contained in the aorta and the carotia, in the neck. These aresensitive to chemical changes that may occur in the blood. If they were todetect a rise in carbon dioxide levels within the blood it would then sendmessages to the brain in order for it to make the appropriate homeostaticresponse to increase the rate and the depth of breathing. This would mean that thecarbon dioxide levels in the blood would decreases as it is being secreted outof the body at a quicker rate. When the carbon dioxide levels within the bodyreturn to normal, the depth and rate of breathing can return to its normal rateto continue to maintain a constant rate. In order to maintain oxygen levels andbreathing rate three of the body systems must work together; the nervoussystem, the cardiovascular system and the respiratory system.
The nervoussystem plays a role by receiving the message from the receptors and initiatingthe correct response the appropriate body parts. The cardiovascular system isresponsible for carrying the oxygen within the blood and for transportingcarbon dioxide from the cells of the body back to the alveoli where gaseousexchange takes place to remove the carbon dioxide. Changes in core body temperature are also another naturalhomeostatic response to changes in external environment. Temperature regulationwithin the body is known as thermoregulation. Thermoregulation is an automaticresponse .Average body temperature is 37 degrees Celsius as humans arehomoeothermic or warm blooded.
The hypothalamus is the part of the brain whichcontrols body temperature. Covering the skin are receptors which detect changesin temperature in the outside temperature. These receptors then send messagesto the hypothalamus concerning these changes so that it can send out thecorrect response. When the body temperature becomes too hot, glands produce andrelease sweat and this helps to cool the body down by releasing the heatthrough evaporation. Vasodilatation happens when the body becomes too hot. Whenthe body temperature increases the blood vessels swell or dilate.
This allowsmore of the warm blood to flow near the skins surface. This means that heat canbe lost to the air. This is also the reason for skin to become reddened when weare too hot. The hair muscles relax so that the hairs lie flat in order toallow heat to escape. Sweat is given off and blood flow in the capillaries isincreased. Vasoconstriction is the name for the process which occurswhen the body temperature reduces and we are too cold.
The blood vessels narrowor constrict in order to reduce the flow of the warm blood near to the skinssurface. This means that there is less heat loss by the air and is the reasonwhy skin looks pale when we are cold. The hair muscles underneath the skincause the hairs to stand up in order for them to trap heat. The name for thisis piloerection.
There is also a decreased blood flow in the capillaries andour muscles rapidly contract to warm up the surrounding tissue. This is thecause of shivering when we feel cold. Thyroxin is a hormone which is releasedfrom the thyroid in order to increase temperature. It is very important for ourbody to have these homeostatic responses as out body’s chemical activity beginsto slow when our core body temperature falls below 35 degree Celsius.Finally, blood glucose levels are another process which iscontrolled through homeostasis within the body. Glucose is the name of the mainsugar which is produced by the diet and is made from the food we consume.
Glucose is carried via the bloodstream and is used in order to produce energyfor the cells within the body. The concentration of glucose in the blood isdetected by receptors cells in the pancreas (part of the digestive system). Thepancreas is the organ which is responsible for producing and secreting insulin-insulin is another example of the hormone thyroxin. The body cells need glucoseto be able to function and so this homeostatic mechanism works to keep thebody’s glucose levels at a constant rate for them to work. In the same way asinsulin is used, glucagon increases the concentration of glucose in the blood.Hen glucagon is released it results in glucose being given out by cells. Thepancreas is the part of the body which has the responsibility to send chemicalmessengers to stimulate the release of either insulin or glucagon, depending onwhat is necessary. Insulin also plays the role of motivating the uptake ofglucose by the liver.
In the liver it is converted into glycogen.M2-In this part of the assignment I will discuss the probablehomeostatic responses to change in the internal environment during exercise.When you are exercising different changes occur in the body in order to be ableto deal with the change in the environment and the reaction that occurs in thebody.
Homeostasis is for the process of the body to maintain a consistentinternal state. The nervous system sends and receives signals abouttemperature, hydration, blood pressure and much more factors. The endocrinesystem carries chemical messengers to transmit body functions. During any formof exercise, the body’s internal environment is altered and places under aconsiderable amount of stress. Through the homeostatic feedback mechanisms, thebody is able to maintain a healthy internal environment and quickly return tonormal after the exercise ends.
These homeostatic mechanisms respond to exercise withchanges in the heart rate, respiration, oxygen consumption, carbon dioxide,pulse rate, blood pressure and body temperature.During the exercise, the body requires more oxygen and alsosmooth removal of care dioxide. In order to meet his respiratory systemresponds to changes in the breathing rate. The cardiovascular system modifiesthe heart rate , blood pressure and capillary beds to maintain the bodytemperature around 37 degrees and blood pressure roughly around 120/80mmgh.
The probable homeostatic responses to changes in theinternal environment during exercise to the heart rate, your body’s workingmuscles require additional stores of oxygen to help feed their energyrequirements. The body receives oxygen from the lungs and transmits it to yourmuscles through your bloodstream. The heart controls the flow of bloodthroughout the body and your heart rate is a factor of that flow. Thereforewhen your muscles work harder and require more oxygen, your heart rateincreases to meet the needs to maintain a consistent internal state, the harderyou work the faster your heart pumps.The probable homeostatic responses to changes in theinternal environment during exercise to the breathing rate, exercise willincrease the demands on your body to supply the fuel it needs to perform. Yourbody’s need for oxygen will increase. As the demand increases, your breathingrate will increase as your body attempts to exercise efficiently and provide areasonable amount of oxygen to cells.
The cardiovascular system will alsoadjust to provide energy and remove wastes including carbon dioxide frombreathing.The probable homeostaticresponses to changes in the internal environment during exercise to bodytemperature, exercises causes your body system for regulating temperature tokick into high gear. Heat production by the body can cause your internaltemperature to rise up to 40°celcius.
Your body has internal processes thatallow for control over this rise. The probable homeostatic responses to changes in theinternal environment during exercise to blood glucose levels to fall, due tothe body drawing from fuel not only fat but also from glucose stores which isfound in the blood, muscles and the liver. Sugar is first drawn from the blood;even short bursts of exercise can cause a temporary blood glucose drop. Themore intense, longer lasting exercise sessions depletes glycogen deposits inthe liver. It can take up to 24 hours for the body to replenish these stores,which leaves you at an increased risk for a post-exercise blood sugar drop.D2Homeostasis is important in maintaining good health becauseit maintains cellular function. If the cells in our body weren’t at the righttemperature and don’t receive enough oxygen they wouldn’t function properly andeventually they would die.
Negative feedback is vital in maintaining homeostasisbecause when a certain factor within the body varies from the norm, receptorsdetect it and send a message through either the parasympathetic or sympatheticnervous system to start corrective mechanisms to restore it back to the norm.For example, if a person gets too cold the receptors detect this sending amessage through the sympathetic nervous system causes the hairs on your body toraise trapping air to keep the body warm and it sends a message to your musclesso they spasm to produce heat. This is important because if your body gets toocold your cells can’t maintain cellular function and would become denatured.The optimum temperature for the body is 37 degrees Celsius so is yourtemperature drops below temperature it won’t be able to function at a healthylevel.
This is known as hypothermia.Hypothermia can also put the body at risk. If the body risesabove the optimum temperature your cells cannot maintain healthy cellularfunction and would become denatured. Receptors pick this negative feedback upand send a message through the sympathetic nervous system to flatten the hairon your body to increase conductivity, it causes the sweat glands to secreteliquid which evaporates of your body to cool you down and it causes yourcapillaries to rise to the surface of your skin to radiate heat to help coolthe body down. All of this help to regulate your body’s temperature to maintaingood cellular function therefore maintaining healthy functioning of the body.Homeostasis is also responsible for keeping the heartbeating at a steady pace. A normal healthy heart rate for most people is 60-100bpm. If someone is doing exercise it is normal for the heart rate to increasebecause chemoreceptors detect an increase in pH and carbon dioxide in the bloodso a message is sent through the sympathetic nervous system to the sinoatrial(SA) node and the adrenal gland secretes epinephrine and norepinephrine to makethe heart beat faster to supply the body’s cells with oxygen.
It’s also normalfor the heart rate to decrease when someone is sleeping because the sympatheticnervous system becomes less dominant and the parasympathetic nervous systemtakes over which causes the heart rate to slow. But, overall 60-100 bpm is ahealthy heart rate and if it drops below this when someone’s not resting itcould mean that they have bradycardia which could cause heart failure, syncope(loss of consciousness/fainting), angina and high blood pressure. If someone’sheart rate was too fast they could have tachycardia which could causedizziness/light-headedness, heart palpitations, angina, shortness of breath,unconsciousness and cardiac arrest. So it’s important for homeostasis toregulate the hearts bpm because otherwise you would not have a healthy functioningbody.Homeostasis is also responsible for regulating a person’sbreathing rate. A normal, healthy breathing rate for most adults is between8-16 breathes per minute.
It’s normal for the breathing rate to increase duringexercise because chemoreceptors detect an increased pH and carbon dioxide inthe blood so a message is sent through the sympathetic nervous system to thediaphragm and intercostal muscles to make the move faster causing the breathingrate to go up so that the body can get more oxygen. It’s also normal for aperson’s breathing rate to be lower than the norm whilst they’re sleepingbecause the sympathetic nervous system becomes less dominant so theparasympathetic nervous system takes over causing the breathing rate todecrease. But whilst awake the norm is between 8-16 breathes per minute.
Ifsomeone’s breathing rate is less than this they have bradypnea which could becaused by many health problems such as high blood pressure/hypertension. Ifsomeone’s breathing rate is too fast they have tachypnea which could be causedby many health problems such as hypoglycaemia. So, it’s important forhomeostasis to regulate breathing rate because having either bradypnea ortachypnea means that the body is not functioning healthily leading to an arrayof health problems.To conclude, if homeostasis did not regulate systems withinthe body and react to negative feedback it would cause many health problems andcellular function couldn’t be maintained so it would easily lead to death,therefore, homeostasis is vital in maintaining the healthy functioning of thebody.