The actual word homeostasis means “steady state”. Homeostasis describes how the body regulates its process to keep its internal conditions as stable as possible. Homeostasis is necessary because human cells are efficient but very demanding. The phrase homeostasis is a bit confusing; conditions inside our bodies are not constant but are kept within a narrow range. Some factors such as temperature and blood PH change slightly while others such as blood glucose very considerably throughout a normal day without producing any harmful effects.
A brief description of homeostasis is that it is maintenance of a constant internal environment in response to a change in external environment. Negative feed makes sure that as levels return to normal, corrective mechanisms are scaled down, it’s when the body maintains conditions within particular limits, and the body will do this by opposing a change that deviates from the normal, core temperature falls. Core temperature rises, drop detected by hypothalamus. Brain sends signals to the body that brings out shivering and vasoconstriction.
Temperature turns to normal. Normal body temperature: 36.9c
Rise detected by hypothalamus. Brain sends signals to body that brings out sweating and vasodilatation. Negative feedback comes when an important variable, sometimes known as a key variable such as the pH of blood and tissue fluid.Homeostasis is the process of maintaining a constant internal environment in response to changes in the external environment. Homeostatic mechanisms are for regulating; body temperature, blood glucose, heart rate and breathing rate. Regulating the internal environment of a human is achieved by negative feedback; this is a constant process.
Conditions within the body changes and receptors detect that change; receptors are found in the skin, around vital organs and the hypothalamus. This information of change that is detected by the receptors are then passed to the control centre in the hypothalamus which monitors the changes, when the change in environment fall too far outside the normal range of values the negative feedback response begins. The control centre signals an effecter to take action that will return the system back to its ‘normal’ state.
An example of homeostasis taking place is when a human goes into a cold environment, conditions change internally; the skin, a receptor will detect the change and cold blood will pass to the control centre, hypothalamus. The hypothalamus then monitors this change and signals the effectors if the internal environment goes below minimum core temperature for cells to work properly; thirty-five Degrees Celsius, anything below can be very dangerous. The effectors will heat the body temperature up, making hairs stand up to trap air to create insulation, sweat secretion is reduce so less cooling of the body and blood vessels constrict which reduces the amount of blood near the surface of the skin so the blood can heat up.
All of these effectors enable the human body to go back to its normal state. The opposite example of this is if a human does exercise, every time the muscles, receptor contract, energy is produce which is transformed into heat. Heat from muscles then moves to the blood which circulates throughout the body which makes temperature rise. When you are exercising different changes occur in the body to try and deal with the change in the environment and the reaction that occurs in the body. I will also explain the homeostatic mechanisms when someone exercises. Homeostasis is for the process of the body to maintain a relatively consistent internal state. The nervous system sends and receives signals about temperature, hydration, blood pressure and much more factors. The endocrine system carries chemical messengers to adjust bodily functions. During forms of exercise, the body’s internal environment is altered and placed under a considerable amount of stress.
Through homeostatic feedback mechanisms, the body is able to maintain a healthy internal environment and quickly return to normal after exercise ends. These homeostatic mechanisms respond to exercise with changes in the heart rate, respiration, oxygen consumption, carbon dioxide clearance, pulse rate, blood pressure and body temperature. During exercise, the body requires more oxygen and smooth removal of care dioxide. To meet this, the respiratory system responds by changes in breathing rate.
The cardiovascular system modifies heart rate, blood pressure and capillary beds to maintain body temperature around 37 degrees and blood pressure roughly around 120/80mmhg. The probable homeostatic responses to changes in the internal environment during exercise to the heart rate, your body’s working muscles require additional stores of oxygen to help feed their energy requirements. The body receives oxygen from the lungs and transmits it to your muscles through your bloodstream. The heart controls the flow of blood throughout the body and your heart rate is a factor of that flow.
Blood glucose the glucose in your blood (also known as blood sugar, and another form of carbohydrate in your body) can sometimes be used as an energy source to make ATP. During exercise your body prefers to maintain your blood glucose levels by several different actions rather than use it for energy.
Actions such as increased levels of epinephrine, glucagon and cortisol that get released in your body during exercise act to maintain your blood glucose levels through special pathways in the liver and also encourage your muscles to use more glucose (which is good because you can keep working out!). Sometimes though, if you fail to eat correctly before your workout or have low muscle glycogen levels (because you’re not eating right in the several hours after exercise), you may experience drops in your blood glucose levels that make you feel tired, shaky, cold, irritable and unable to exercise any longer.
Some of the key factors that dictate if your blood sugars will crash or not include:
The timing of your last meal before your workout (when). The composition of your last meal before your workout (what). How your body responded to food you ate before your workout (how). When and what you ate in the hours following your last workout. If you wait too long after your last meal or snack to exercise, you’re more likely to experience drops in your blood sugar levels because they’re already feeling weak and require food to be maintained. This results in a major drop in exercise performance.
If somebody remains in the cold temperatures for a long period of time, the thermostat homeostasis mechanisms may fail and you could develop hypothermia. Hypothermia is when your body temperature drops beyond below the standard temperature needed for your body to function accurately without any inner body catastrophes. When your body temperature reaches a certain point below the norm, usual actions can’t work, including homeostasis. When your body is put in a certain situation for too long your internal environment may begin to shut down, leaving your body vulnerable. Unless immediate action is taken to bring the homeostasis back to normal you will die. The same thing would happen if your body was exposed to extreme heat for any long periods of time. For the metabolic system to continue to occur in the body cells need a constant supply of glucose.
Glucose is a carbohydrate, and is the most important simple sugar in human metabolism. Blood sugar levels should be maintained at around 90mg of glucose per 100ml of blood. If blood glucose levels rise, insulin is released into the blood. Insulin is one of many hormones that help the body turn the food we eat into energy. Also, insulin helps us store energy that we can use later. After we eat, insulin works by causing sugar (glucose) to go from the blood into our body’s cells to make fat, sugar, and protein. When we need more energy between meals, insulin will help us use the fat, sugar, and protein that we have stored. Insulin is produced by our own insulin that is made in the pancreas gland or taken by injection.