Homeostasis

Homeostasis The regulation of an organism’s internal environment to maintain conditions suitable for life. The internal equilibrium of the body, the ultimate gauge of its proper functioning, involves the maintenance of a constant rate of certain molecules in the blood. Disruption of homeostasis of the body systems can cause disease and possibly death. Body temperature, pH Levels and hormone levels are examples of mechanisms that are regulated by the body to maintain homeostasis.

Maintaining homeostasis of body temperature The hypothalamus maintains body temperature. Too warm- perspire and lose heat by evaporation Too cold- shiver and increase metabolism to generate heat Too much heat can result in heatstroke. During this condition body temperatures can reach 110 °F, as the body loses it’s ability to rid itself of heat. Skin becomes hot and dry Blood rushes to head and face Convulsions, brain damage, and death may follow

Hypothalmus gland in the frog

Maintaining homeostasis of body temperature Too little heat can result in hypothermia. During this condition, body temperature falls below 95°F. If the body’s core temperature falls below 90°F the heart can’t pump blood and it will contract erratically.

Maintaining homeostasis of hormone levels The endocrine system plays an important role in the maintenance of homeostasis. Example: glucagon and insulin maintain a balanced blood glucose level. These hormones are considered antagonistic because their actions have opposite effects. Increase in glucose concentration following glucagon secretion is counteracted by an insulin secretion.

Maintaining homeostasis of hormone levels Most hormones use negative feedback which is the release of an initial hormone stimulates the release or production of other hormones or substances that inhibit further release of the initial hormone.