Lifestyle and Health: Homeostasis

• Homeostasis is a concept in biology that involves maintaining a constant internal environment in response to changes in external conditions. This process is essential for the survival and functioning of organisms.

• Homeostasis regulates a range of conditions within the body, such as temperature, blood glucose levels, water balance and blood ion concentration. These aspects are controlled through negative feedback mechanisms, which aim to restore balance if the body deviates from the ideal conditions.

• Body temperature is maintained at around 37 degrees Celsius in humans. If the body temperature increases, the skin responds by causing you to sweat to cool down. If the body temperature decreases, the body shivers to generate heat.

• Blood glucose levels are regulated by insulin. If blood glucose levels increase, for instance after a meal, insulin is released by the pancreas to lower blood glucose. If blood glucose levels fall, glucagon is released instead to increase glucose levels.

• When you’re dehydrated, your body produces a hormone called ADH which makes the kidneys reabsorb more water to hold onto it. When you’re well hydrated, less ADH is produced, allowing more water to be released in urine.

• If the blood contains too much or too little salt, water balance is affected. The kidneys step in to remove excess ions and store them until they can be expelled from the body.

• Nerves and hormones are primary components in homeostasis. The nervous system can react quickly to changes, while hormones provide a slower, longer-term response.

• Disorders can occur in the body when homeostasis fails. For instance, if insulin is not produced in the right amount or cannot be used effectively, blood sugar levels can rise and result in diabetes.

• Healthy living can assist in maintaining balance in the body. Regular exercise helps regulate body temperature and metabolise glucose, while a balanced diet can ensure a steady supply of the nutrients necessary for the body’s systems to function optimally. Drinking plenty of water can assist with water balance and normal kidney function.

• It’s important to note that each organism has different homeostatic processes depending on their specific needs. For example, cold-blooded amphibians and reptiles don’t regulate their body temperature internally like mammals do, but instead rely on environmental conditions.