What are the two ways by which homeostasis is maintained?
2 Answers
Shivering and insulin secretion.
Explanation:
There are many, many ways that the human body attempts to maintain homeostasis. But what is homeostasis? Homeostasis is the ideal stable conditions for the human body, like the normal body temperature of
Example 1: Body Temperature
Say it's an extremely cold day outside, with snow falling everywhere, and you decide to step outside without a coat or any warm clothes on. Once you step outside, you may start shivering. Shivering is essentially rapid contraction of skeletal muscles, and it produces heat since most muscle activity generates heat. When you step outside, your body begins to shiver to warm you up, so you can maintain a stable body temperature of
Example 2: Insulin and Glucose
After spending all that time outside in the cold, you feel extremely hungry (because shivering and all muscle activity requires energy) so you decide to get a Big Mac. Once you finish eating your burger, your gastrointestinal tract breaks down the burger into a variety of compounds, including glucose, a type of sugar. Your body needs to maintain a stable blood glucose level ,and as glucose enters your bloodstream, your body (specifically the pancreas) releases a compound called insulin to convert the glucose into glycogen. Converting glucose to glycogen, which can be stored and processed easier, helps the body maintain steady blood glucose levels.
Both examples describe how your body experiences a change in conditions (called a stimulus), which leads to your body attempting to return to a normal state and maintain homeostasis. For the glucose example, the change was an increase in blood glucose levels, the body's reaction was releasing insulin, and the stable condition was regular blood glucose level. In the cold weather example, the stimulus was the low temperature, which your body responded to by shivering, and returning to normal temperature.
Homeostasis is maintained by hypothalamus of brain.
Explanation:
Hypothalamus controls homeostasis by two ways:
1. through optimizing levels of hormones in blood,
2. through autonomic motor control.
Changes in internal environment act as stimuli and information reaches the brain/hypothalamus through sensory nerves.
- The response could be delivered immediately to effector organs through autonomic nerves (part of autonomic nervous system).
ANS is a motor outlet and can enhance or suppress activity of effectors through sympathetic or parasympathetic neurons.
- Hypothalamus also releases neurohormones in response to such changes: which in turn influence secretion of both anterior and posterior pituitary.
Hypothalamic neurohormones act as releasing factors for anterior pituitary, while such neurohormones are directly secreted by posterior pituitary.
Concentration of hormone in blood acts as feedback and is constantly monitored by hypothalamus.
